arch-arm: Add explicit AArch64 MiscReg banking

Change-Id: I89836d14491a51b1573f45c8012e3ad12b107d24
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20623
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: Use same template across all MSR inst

Change-Id: Ifb9f1db288e401761b71ccf426e370c475e5663f
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20622
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: Replace occ of opModeToEL(currOpMode/cpsr) with currEL

Change-Id: I739a9be03ea5caa63540c62fd110eee86a058c4c
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20252
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: Added LD/ST<op> atomic instruction family and SWP instrs

Adding LD/ST/SWP family of instructions, LD/ST include a set of
operations like ADD/CLR/EOR/SET/UMAX/UMIN/SMAX/SMIN
This commit includes:
+ Instruction decode
+ Instruction functional code
+ New set of skeletons for Ex/Com/Ini/Constructor and declaration.

Change-Id: Ieea8d4256807e004d2f8aca8f421b3df8d76b116
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19812
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch-arm: Adding CAS/CASP AMO instr including new TypedAtomic func

CAS/CASP atomic instruction implementation
This change includes:
+ Instructions decode
+ new amo64.isa file where CAS/CASP main functional code is implemented
+ mem64.isa include Execute/complete/initiatie skeletons,
contructor and declarator
+ Added TypedAtomic function for pair register CASP instruction

Change-Id: I4a4acdec4ab1c8b888f10ef5dc1e896be8c432bf
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19811
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch-arm: Implement ARMv8.1-PAN, Privileged access never

ARMv8.1-PAN adds a new bit to PSTATE. When the value of this PAN state
bit is 1, any privileged data access from EL1 or EL2 to a virtual memory
address that is accessible at EL0 generates a Permission fault.
This feature is mandatory in ARMv8.1 implementations.
This feature is supported in AArch64 and AArch32 states.
The ID_AA64MMFR1_EL1.PAN, ID_MMFR3_EL1.PAN, and ID_MMFR3.PAN fields
identify the support for ARMv8.1-PAN.

Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Change-Id: I94a76311711739dd2394c72944d88ba9321fd159
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19729
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: Rewrite MSR immediate instruction class

MSR <pstatefield>, #imm is used for setting a PSTATE field using an
immediate. Current implementation has the following flaws:

* There is no base MSR immediate definition: all the existing
PSTATE fields have a different class definition
* Those implementation make use of a generic data64 base class
which results in a wrong disassembly (pstate register is printed as an
integer register).

This patch is fixing this by defining a new base class (MiscRegImmOp64)
and new related templates. In this way, we aim to ease addition of new
PSTATE fields (in ARMv8.x)

Change-Id: I71b630ff32abe1b105bbb3ab5781c6589b67d419
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19728
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: Fix reg dependency for SVE gather microops

The first microop of an SVE gather creates a copy of the
source vecreg into AA64FpUreg0. The subsequent microops
must refer to this copy as a source in order to establish
the correct register dependencies.

Change-Id: I84d8c331f9f9ebca609948a15f686a7cde67dc31
Signed-off-by: Gabor Dozsa <gabor.dozsa@arm.com>
Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19172
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: Add SVE LD1RQ[BHWD]

Add both scalar+scalar and scalar+immediate versions.

Change-Id: If5fa1a71ab0dab93f9d35b544ea0899ece858bea
Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19170
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Add support for SVE load/store structures

Change-Id: I4d9cde18dfc3d478eacc156de6a4a9721eb9e2ff
Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/13524
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Add first-/non-faulting load instructions

First-/non-faulting loads are part of Arm SVE.

Change-Id: I93dfd6d1d74791653927e99098ddb651150a8ef7
Signed-off-by: Gabor Dozsa <gabor.dozsa@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19177
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: Move the memacc_code before op_wb in fp loads

This is trying to fix the bug that arises when a memory exception
is generated during a fp flavoured load (A memory load targeting
a SIMD & FP register).
With the previous template a fault was not stopping the register
value to be modified (wrong)

if (fault == NoFault) {
fault = readMemAtomic(xc, traceData, EA, Mem, memAccessFlags);
%(memacc_code)s;
}

if (fault == NoFault) {
%(op_wb)s;
}

The patch introduces a Load64FpExecute template which is moving the
register write (memacc_code) just before the op_wb

Change-Id: I1c89c525dfa7a4ef489abe0872cd7baacdd6ce3c
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19228
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: Add initial support for SVE gather/scatter loads/stores

Change-Id: I891623015b47a39f61ed616f8896f32a7134c8e2
Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/13521
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: Change mcrMrc15TrapToHyp signature

This patch is moving MiscRegs reading inside the mcrMrc15TrapToHyp
helper function. Rather than passing registers as arguments,
we are just passing a ThreadContext pointer

Change-Id: I6636dd3a4f92f757479d8a8d2c47de050a0b9eae
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17988
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: implement VMINNM and VMAXNM scalar version

ARMv8.2 16-bit versions have not yet been implemented, but a placeholders
were created for them.

Refactor the nearby decoding tree to closely match the ARM spec A32 decode
table.

That piece of the tree can also be called from thumb which decodes it in
the same way, although the thumb decode table has a different terminology

The old code didn't match neither A32 or T32 terminologies, so it is
better to at least match one of them to help verify correctness.

Change-Id: Iabbbca2932557cf6c98ce36690c385c3ddf39ed8
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18690
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: implement VMINNM and VMAXNM SIMD version

This instruction is backported from aarch64.

In order to use the existing fplibMinNum backend, we first move
VMIN and VPMIN to use fplib. Adding VMINNM is then trivial.

Change-Id: I404daabeb6079f60e51a648a06d5b3e54f1c24a9
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18689
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: Add initial support for SVE contiguous loads/stores

Thanks to Pau Cabre and Adria Armejach Sanosa for their contribution
of bugfixes.

Change-Id: If8983cf85d95cddb187c90967a94ddfe2414bc46
Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/13519
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch: Stop using TheISA within the ISAs.

We know for sure what the ISA is, so there's no need for the
indirection.

Change-Id: I73ff04c50890d40a4c7f40caeee746b68b846cb3
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18488
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

dev-arm: Correct cast of template parameter

Clang with -Wconstant-conversion is _very_ restrictive on casting.
The shift operator results in an incorrect promotion.

This patch add a compile-time static cast that remove the error
when clang is used.

Change-Id: I3aa1e77da2565799feadc32317d5faa111b2de86
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17308
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Fix use of bitwise operators on booleans

Change-Id: I3762b2921f1d00a9104d8dc11a19dc0a219581e5
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17288
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm,cpu: Add initial support for Arm SVE

This changeset adds initial support for the Arm Scalable Vector Extension
(SVE) by implementing:
- support for most data-processing instructions (no loads/stores yet);
- basic system-level support.

Additional authors:
- Javier Setoain <javier.setoain@arm.com>
- Gabor Dozsa <gabor.dozsa@arm.com>
- Giacomo Travaglini <giacomo.travaglini@arm.com>

Thanks to Pau Cabre for his contribution of bugfixes.

Change-Id: I1808b5ff55b401777eeb9b99c9a1129e0d527709
Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/13515
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: implement floating point aarch32 VCVTA family

These instructions round floating point to integer, and were added to
aarch32 as an extension to ARMv7.

Change-Id: I62d1705badc95a4e8954a5ad62b2b6bc9e4ffe00
Reviewed-on: https://gem5-review.googlesource.com/c/16788
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Implement LoadAcquire/StoreRelease in AArch32

This patch is implementing LoadAcquire/StoreRelease instructions in
AArch32, which were added in ARMv8-A only and where not present in
ARMv7.

Change-Id: I5e26459971d0b183a955cd7b0c9c7eaffef453be
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15817
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: IsStoreConditional flag set depending on flavor

This patch is aligning A32 with A64 where the IsStoreConditional flag
doesn't have to be specified manually in the instruction implementation,
but will be automatically added to any exclusive store.

Change-Id: Id02ed6fc2beeca6d125017393714a7c6eb3d8a33
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15816
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Remove SWP and SWPB instructions

The SWP and SWPB instructions have been removed from AArch32. It was
previously (ARMv7) possible to enable them with the ID_ISAR0.Swap bits,
which are now hardcoded to 0b0000 (SWP and SWPB not implemented)

Change-Id: Ic32b534454a7e0f7494a6f0b5e11182c65b3fe24
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15815
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arm: Stop using the FloatReg and FloatRegBits types.

This will let us make those types 64 bits to be in line with the other
architectures.

Change-Id: I5aef5199f4d2d5bb1558afedac5c6c92bf95c021
Reviewed-on: https://gem5-review.googlesource.com/c/13621
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch-arm: We add PRFM PST instruction for arm

Note current PRFM supports only PLD, but PST (prefetch for store) is
also important for latency hiding. We also bug fix in disassembler to
display prfop correctly.

Change-Id: I9144e7233900aa2d555e1c1a6a2c2e41d837aa13
Signed-off-by: Yuetsu Kodama <yuetsu.kodama@riken.jp>
Reviewed-on: https://gem5-review.googlesource.com/c/13675
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Refactor AArch64 MSR/MRS trapping

This patch refactors AArch64 MSR/MRS trapping, by moving the trapping
helpers in arch/arm/utility and in the isa code into a MiscRegOp64
class.

This class is the Base class for a generic AArch64 instruction which is
making use of system registers (MiscReg), like MSR,MRS,SYS. The common
denominator or those instruction is the chance that the system register
access is trapped to an upper Exception level. MiscRegOp64 is providing
that feature.

What do we gain? Other "pseudo" instructions, like access to
implementation defined registers can inherit from this class to make use
of the trapping functionalities even if there is no data movement
between GPRs and system register.

Change-Id: I0924354db100de04f1079a1ab43d4fd32039e08d
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13778
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Trap to EL2 only if not in Secure State

MRS/MSR Instructions should trap to EL2 only if we are in non-Secure
state since at the current implementation (Armv8.0) there is no Secure
EL2.

Change-Id: I93af415fbcbd19a470752adf6afc92e520e9645d
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13777
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Fix HVC trapping beahviour

This patch is fixing HVC trapping behaviour, reusing the pseudocode
implementation provided in the arm arm.

Change-Id: I0bc81478400b99d84534c1c8871f894722f547c5
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13776
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: AArch64 Crypto AES

This patch implements the AArch64 AES instructions
from the Crypto extension.

Change-Id: I9143041ec7e1c6a50dcad3f72d7d1b55d6f2d402
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13250
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: AArch64 Crypto SHA

This patch implements the AArch64 secure hashing instructions
from the Crypto extension.

Change-Id: I2cdfa81b994637c880f2523fe37cdc6596d05cb1
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13249
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: AArch32 Crypto AES

This patch implements the AArch32 AES instructions
from the Crypto extension.

Change-Id: I51e6deda748b0c26135bcfe9d0c7128f3af91f3d
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Matt Horsnell <matt.horsnell@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13248
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: AArch32 Crypto SHA

This patch implements the AArch32 secure hashing instructions
from the Crypto extension.

Change-Id: Iaba8424ab71800228a9aff039d93f5c35ee7d8e5
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13247
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Add FP16 support introduced by Armv8.2-A

This changeset adds support for FP/SIMD instructions with
half-precision floating-point operands.

Change-Id: I4957f111c9c5e5d6a3747fe9d169d394d642fee8
Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/13084
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arm: Add support for RCpc load-acquire instructions (ARMv8.3)

Please note that at the moment these instructions behave like the
existing load-acquire instructions, which follow the more conservative
RCsc consistency model. This means that the new instructions are
_functionally_ correct, but the potential performance improvements
enabled by the RCpc model will not be experienced in timing
simulations.

Change-Id: I04c786ad2941072bf28feba7d2ec6e142c8b74cb
Reviewed-by: Andreas Hansson <andreas.hansson@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/11989
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch-arm: AArch32 execution triggering AArch64 SW Break

AArch32 Software Breakpoint (BKPT) can trigger an AArch64 fault when
interprocessing if the trapping conditions are met.

Change-Id: I485852ed19429f9cd928a6447a95eb6f471f189c
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/11197
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: BadMode checking if corresponding EL is implemented

The old utility function called badMode was only checking if the mode
passed as an argument was a recognized mode. It was not checking if the
corresponding mode/EL was implemented. That function has been renamed to
unknownMode and a new badMode has been introduced. This is used by the
cpsrWriteByInstruction function. In this way any try to change the
execution mode won't succeed if the mode hasn't been implemented.

Change-Id: Ibfe385c5465b904acc0d2eb9647710891d72c9df
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/11196
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Read APSR in User Mode

This patch substitutes reads to the CPSR in user mode (MRS CPSR) to
reads to APSR (Application Program Status Register).
This is the user level alias for the CPSR. The APSR is a subset of the
CPSR.

Change-Id: I18a70693aef6fd305a4c4cb3c6f81f331bc60a2d
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/10602
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Fix mrc,mcr to cop14 disassemble

This patch fixes the disassemble for AArch32 mcr/mrc p14 instructions.

Change-Id: If5d7c2d7c726f040ae20053bf1d70f4405b34d0e
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/9681
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arm: Fix maybe-uninitialized GCC warnings

GCC 7 generates maybe-uninitialized warnings at the code that updates
the "dest" variables in the writeVecElem function of neon64_mem.hh file.
It is because the generated code does not appropriately initialize the
output variable before passing it to the writeVecElem function. This
patch initializes the output variable to fix this.

Change-Id: I50a8f4e456ccdcaa3db1392ec097017450c56ecb
Signed-off-by: Chun-Chen Hsu <chunchenhsu@google.com>
Reviewed-on: https://gem5-review.googlesource.com/9121
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: ERET from AArch64 to AArch32 ignore MSBs

The 32 most significant bits of ELR_ELx must be ignored when returning
from AArch64 to AArch32.

Change-Id: I412d72908997916404e16e9eeca2789a9c529e58
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8881
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arm: Remove ignored const qualifier

gcc8 warns about ignored const qualifiers (-Wignored-qualifiers) and
that breaks builds. It was suggested that the warning be moved to
Wextra[1] but that's probably not going to happen anytime soon.

[1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82711

Change-Id: Ib808906deb9a1c2dccb1c34b6563db0c24c66655
Signed-off-by: Siddhesh Poyarekar <siddhesh.poyarekar@gmail.com>
Reviewed-on: https://gem5-review.googlesource.com/8562
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Make hlt64 a mem barrier with semihosting

The HLT instruction is used to trap into semihosting. The semihosting
code can change the contents of memory behind the back of the CPU,
which requires instructions triggering semihosting to be
non-speculative and memory barriers.

Change-Id: I735166251aa194120ad49c08082d4ac65fe96524
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8373
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Add AArch32 HLT Semihosting interface

AArch32 HLT instruction is now able to issue Arm Semihosting commands as
the AArch64 counterpart in either Arm and Thumb mode.

Change-Id: I77da73d2e6a9288c704a5f646f4447022517ceb6
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8372
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Add AArch32 SVC Semihosting interface

AArch32 Svc instruction is now able to issue Arm Semihosting commands as
the AArch64 counterpart in either Arm and Thumb mode.

Change-Id: Ibe47ac23d0c26f3f819cc0e2b3ee874b5cdbb3d3
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8371
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: HLT using immediate when checking for semihosting

HLT can use the immediate field when checking for semihosting,
rather than re-parsing it from the machInst variable.

Change-Id: I072cb100029da34d129b90c5d17e1728f9016c88
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8369
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Fix Hlt64,Svc64,Hvc64,Smc64,Brk64 disassembly

This patch fixes the disassembly of AArch64 Exception Generating
instructions, which were not printing the encoded immediate field. This
has been accomplished by changing their underlying type to a newly
defined one.

Change-Id: If58ae3e620d2baa260e12ecdc850225adfcf1ee5
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8368
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Add aarch64 semihosting support

Add basic support for Arm Semihosting 2.0 simulation calls [1]. These
calls let the guest system call a simulator or debugger to request
OS-like support when running bare metal code.

With the exception of SYS_SYSTEM, this implementation supports all of
the Semihosting 2.0 specification in aarch64.

[1] https://developer.arm.com/docs/100863/latest/preface

Change-Id: I08c153c18a4a4fb9f95d318e2a029724935192a7
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jack Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8147
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch-arm: Fix big endian support in {Load,Store}Double64

{Load, Store}Double64 didn't consider some of the big-endian
situations. Added big-endian related data conversions to correct them.

Change-Id: I8840613f94446e6042276779d1f02350ab57987f
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8145
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Change the type of fault for dc ivac instructions

Change-Id: I00f957a3bc4721a66db62b1257f10e9019a94608
Reviewed-by: Jack Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/7829
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch-arm: Unify permission checks for dc * instructions

Change-Id: Ib47f4134e3f0a580e5356d384a5d3b293c1af7be
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/7828
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Turn dc ivac to dc civac when some conditions are met

The Arm ARM defines that at EL1 a data cache invalidate instruction
performs a data cache clean and invalidate operation if all of the
following apply:
* EL2 is implemented,
* HCR_EL2.VM is set to 1,
* SCR_EL3.NS is set to 1 or EL3 is not implemented.
This changeset implements this behavior.

Change-Id: I6b6aef2f4b1e7eb107c069fdb0a10f4aa8e6b196
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/7826
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Fix printing of the data cache maintenance instructions

Change-Id: I2322c7bf65b38cb07a1ea2b5dc25dfc5a0496cf0
Reviewed-by: Jack Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/7825
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch-arm: Change function name for banked miscregs

This commit changes the function's name used for retrieving the index of a
security banked register given the flatten index. This will avoid confusion
with flattenRegId, which has a different purpose.

Change-Id: I470ffb55916cb7fc9f78e071a7f2e609c1829f1a
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/7982
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Fix AArch32 SETEND Instruction

This patch fixes AArch32 SETEND instruction, which was previously
executed unconditionally without checking (H)SCTLR.SED field. This bit
enables/disables the trapping of the instruction.

Change-Id: Ib3d2194c8d16c34ec2a9ab3e8090081900c1e42e
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/7981
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Removing Serializing flag from ISB

ISB Serializing behaviour is guaranteed by IsSquashAfter,
which is inherently serializing; when instruction is commited,
consecutive instructions are flushed and refetched.

Change-Id: I05e61b4cf9f01113d95b1502c996d04cbd69b759
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5701
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Fixed WFE/WFI trapping behaviour

This patch fixes the WFx trapping behaviour by introducing the arm arm
v8 pseudocode functions: checkForWFxTrap32 and checkForWFxTrap64

Change-Id: I3db0d78b5c4ad46860e6d199c2f2fc7b41842840
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/6622
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arm,sparc,x86,base,cpu,sim: Replace the Twin(32|64)_t types with.

Replace them with std::array<>s.

Change-Id: I76624c87a1cd9b21c386a96147a18de92b8a8a34
Reviewed-on: https://gem5-review.googlesource.com/6602
Maintainer: Gabe Black <gabeblack@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

arm: Add support for the dc {civac, cvac, cvau, ivac} instr

This patch adds support for decoding and executing the following ARMv8
cache maintenance instructions by Virtual Address:
* dc civac: Clean and Invalidate by Virtual Address to the Point
of Coherency
* dc cvac: Clean by Virtual Address to the Point of Coherency
* dc cvau: Clean by Virtual Address to the Point of Unification
* dc ivac: Invalidate by Virtual Addrsess to the Point of Coherency

Change-Id: I58cabda37f9636105fda1b1e84a0a04965fb5670
Reviewed-by: Sudhanshu Jha <sudhanshu.jha@arm.com>
Reviewed-by: Stephan Diestelhorst <stephan.diestelhorst@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5060
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

arm: Add support for the mcr dc{ic,i,c}mvac, dccmvau instructions

This patch adds support for the ARMv7 cache maintenance
intructions:
* mcr dccmvac cleans a VA to the PoC
* mcr dcimvac invalidates a VA to the PoC
* mcr dccimvac cleans and invalidates a VA to the PoC
* mcr dccmvau cleans a VA to the PoU

Change-Id: I6511f203039ca145cc9128ddf61d09d6d7e40c10
Reviewed-by: Stephan Diestelhorst <stephan.diestelhorst@arm.com>
Reviewed-by: Anouk Van Laer <anouk.vanlaer@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5059
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

arch-arm: Add support for the brk instruction

Add support for software breakpoints as signalled by the aarch64 brk
instruction. This introduces a new SoftwareBreakpoint fault.

Change-Id: I93646c3298e09d7f7b0983108ba8937c7331297a
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5721
Reviewed-by: Giacomo Gabrielli <Giacomo.Gabrielli@arm.com>

arch-arm: HVC instruction undefined in secure EL1

Since EL2 is not available in secure mode, any HVC call from secure mode
should be treated as undefined. This behaviour was implemented in
aarch32 HVC but not in 64 bit version

Change-Id: Ibaa4d8b1e8fe01d2ba3ef07494c09a4d3e7e87b0
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5921
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Fix MSR/MRS disassemble

This patch is fixing the Aarch64 MSR/MRS disassemble, which was
previously printing unexisting integer registers as source/destination
operands rather than the system register name

Change-Id: Iac9d5f2f2fea85abd9a398320ef7aa4844d43c0e
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5861
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Dsb instruction shouldn't flush the pipeline

DSB Instruction shouldn't flush the pipeline, hence the IsSquashAfter
attribute will be removed for either the 32 and 64 bit version.

Change-Id: I98b2b8bc78aa28445ed1a9b5f34645f8d71616ad
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5363
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Removing FlushPipe fault, using SquashAfter

This Patch is removing the FlushPipe ArmFault, which was used for
flushing the pipeline in favour of the general IsSquashAfter StaticInstr
flag. Using a fault was preventing tracers from tracing barriers like
ISB and from adding them to the instruction count

Change-Id: I176e9254eca904694f2f611eb486c55e50ec61ff
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5361
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arm: Add support for armv8 CRC32 instructions

This patch introduces the ARM A32/T32/A64 CRC Instructions, which are
mandatory since ARMv8.1. The UNPREDICTABLE behaviours are implemented as
follows:
1) CRC32(C)X (64 bit) instructions are decoded as Undefined in Aarch32
2) The instructions support predication in Aarch32
3) Using R15(PC) as source/dest operand is permitted in Aarch32

Change-Id: Iaf29b05874e1370c7615da79a07f111ded17b6cc
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5521
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

alpha,arm,mips,power,riscv,sparc,x86: Merge exec decl templates.

In the ISA instruction definitions, some classes were declared with
execute, etc., functions outside of the main template because they
had CPU specific signatures and would need to be duplicated with
each CPU plugged into them. Now that the instructions always just
use an ExecContext, there's no reason for those templates to be
separate. This change folds those templates together.

Change-Id: I13bda247d3d1cc07c0ea06968e48aa5b4aace7fa
Reviewed-on: https://gem5-review.googlesource.com/5401
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Alec Roelke <ar4jc@virginia.edu>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: RBIT instruction using mirroring func

The high speed bit-reversing function is now used
for the Aarch64/32 RBIT instruction implementation.

Change-Id: Id5a8a93d928d00fd33ec4061fbb586b8420a1c1b
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5262
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

arch-arm: Signal an event when executing store exclusives

When a store exclusive is executed, whether it is successful or not,
the exclusives monitor is cleared and therefore we need to signal an
event for the PE.

Change-Id: I383c88c769c0ac5f5d36c4b5d39c9681134d3a20
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/4480
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: fix ldm of pc interswitching branch

The LDM instruction that loads to the PC causes a branch to the
instruction. In ARMv5T+ the branch can interswitch Thumb and ARM modes.
The interswitch is broken prior to this commit, with LDM to the PC
ignoring the switch.

Change-Id: I6aad073206743f3435c9923e3e2218bfe32c7e05
Reviewed-on: https://gem5-review.googlesource.com/3520
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

arch: ISA parser additions of vector registers

Reiley's update :) of the isa parser definitions. My addition of the
vector element operand concept for the ISA parser. Nathanael's modification
creating a hierarchy between vector registers and its constituencies to the
isa parser.

Some fixes/updates on top to consider instructions as vectors instead of
floating when they use the VectorRF. Some counters added to all the
models to keep faithful counts.

Change-Id: Id8f162a525240dfd7ba884c5a4d9fa69f4050101
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2706
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

cpu: Simplify the rename interface and use RegId

With the hierarchical RegId there are a lot of functions that are
redundant now.

The idea behind the simplification is that instead of having the regId,
telling which kind of register read/write/rename/lookup/etc. and then
the function panic_if'ing if the regId is not of the appropriate type,
we provide an interface that decides what kind of register to read
depending on the register type of the given regId.

Change-Id: I7d52e9e21fc01205ae365d86921a4ceb67a57178
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
[ Fix RISCV build issues ]
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2702

arch-arm: Fix some poorly done type max and min in NEON

The ISA code for ARM calculates min and max elements for types using
bit manipulation. That triggers some warnings, treated as errors, as
the compiler can tell that there is an overflow and the sign
flips. Fixed using standard lib definitions instead.

Change-Id: Ie2331b410c7f76d4bd87da5afe9edf20c8ac91b3
Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3481
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

base, sim, arch: Fix clang 5.0 warnings

Compiling gem5 with recent version of clang (4 and 5) triggers
warnings that are treated as errors:

* Global templatized static functions result in a warning if they
are not used. These should either be declared as static inline or
without the static identifier to avoid the warning.

* Some templatized classes contain static variables. The
instantiated versions of these variables / templates need to be
explicitly declared to avoid a compiler warning.

Change-Id: Ie8261144836e94ebab7ea04ccccb90927672c257
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/3420
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

arm: Don't panic when checking coprocessor read/write permissions

Instructions that use the coprocessor interface check the current
program status to determine whether the current context has the
priviledges to read from/write to the coprocessor. Some modes allow
the execution of coprocessor instructions, some others do not allow it,
while some other modes are unexpected (e.g., executing an AArch32
instruction while being in an AArch64 mode).

Previously we would unconditionally trigger a panic if we were in an
unexpected mode. This change removes the panic and replaces it
with an Undefined Instruction fault that triggers if and when a
coprocessor instruction commits in an unexpected mode. This allows
speculative coprocessor instructions from unexpected modes to execute
but prevents them from gettting committed.

Change-Id: If2776d5bae2471cdbaf76d0e1ae655f501bfbf01
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Rekai Gonzalez Alberquilla <rekai.gonzalezalberquilla@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2281
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Weiping Liao <weipingliao@google.com>

arm: Fix DPRINTFs with arguments in the instruction declarations

Change-Id: I0e373536897aa5bb4501b00945c2a0836100ddf4
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>

cpu, arm: Distinguish Float* and SimdFloat*, create FloatMem* opClass

Modify the opClass assigned to AArch64 FP instructions from SimdFloat* to
Float*. Also create the FloatMemRead and FloatMemWrite opClasses, which
distinguishes writes to the INT and FP register banks.
Change the latency of (Simd)FloatMultAcc to 5, based on the Cortex-A72,
where the "latency" of FMADD is 3 if the next instruction is a FMADD and
has only the augend to destination dependency, otherwise it's 7 cycles.

Signed-off-by: Jason Lowe-Power <jason@lowepower.com>

isa,arm: Add missing AArch32 FP instructions

This commit adds missing non-predicated, scalar floating point
instructions. Specifically VRINT* floating point integer rounding
instructions and VSEL* floating point conditional selects.

Change-Id: I23cbd1389f151389ac8beb28a7d18d5f93d000e7
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nathanael Premillieu <nathanael.premillieu@arm.com>

arm: Add m5_fail support for aarch64

Change-Id: Id2acbc09772be310a0eb9e33295afab07e08a4fa
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

arm: Fix trapping to Hypervisor during MSR/MRS read/write

This patch restricts trapping to hypervisor only if we are in the
correct exception level for the trap to happen.

Change-Id: I0a382b6a572ef835ea36d2702b8a81b633bd3df0

arm: Add AArch64 hypervisor call instruction 'hvc'

This patch adds the AArch64 instruction hvc which raises an exception
from EL1 into EL2. The host OS uses this instruction to world switch
into the guest.

Change-Id: I930ee43f4f0abd4b35a68eb2a72e44e3ea6570be

arm: Rewrite ERET to behave according to the ARMv8 ARM

The ERET instruction doesn't set PSTATE correctly in some cases
(particularly when returning to aarch32 code). Among other things,
this breaks EL0 thumb code when using a 64-bit kernel. This changeset
updates the ERET implementation to match the ARM ARM.

Change-Id: I408e7c69a23cce437859313dfe84e68744b07c98
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nathanael Premillieu <nathanael.premillieu@arm.com>

arm: Correctly check FP/SIMD access permission in aarch32

The current implementation of aarch32 FP/SIMD in gem5 assumes that EL1
and higher are all 32-bit. This breaks interprocessing since an
aarch64 EL1 uses different enable/disable bits. This change updates
the permission checks to according to what is prescribed by the ARM
ARM.

Change-Id: Icdcef31b00644cfeebec00216b3993aa1de12b88
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Mitch Hayenga <mitch.hayenga@arm.com>
Reviewed-by: Nathanael Premillieu <nathanael.premillieu@arm.com>

misc: Fix issues flagged by gcc 6

A few warnings (and thus errors) pop up after being added to -Wall:

1. -Wmisleading-indentation

In the auto-generated code there were instances of if/else blocks that
were not indented to gcc's liking. This is addressed by adding braces.

2. -Wshift-negative-value

gcc is clever enougn to consider ~0 a negative constant, and
rightfully complains. This is addressed by using mask() which
explicitly casts to unsigned before shifting.

That is all. Porting done.

arm: Squash after returning from exceptions in v7

Properly done for the ERET instruction in v8, but not for v7.
Many control register changes are only visible after explicit
instruction synchronization barriers or exception entry/exit.
This means mode changing instructions should squash any
younger in-flight speculative instructions.

pseudo inst,util: Add optional key to initparam pseudo instruction

The key parameter can be used to read out various config parameters from
within the simulated software.

isa: Add parameter to pick different decoder inside ISA

The decoder is responsible for splitting instructions in micro
operations (uops). Given that different micro architectures may split
operations differently, this patch allows to specify which micro
architecture each isa implements, so different cores in the system can
split instructions differently, also decoupling uop splitting
(microArch) from ISA (Arch). This is done making the decodification
calls templates that receive a type 'DecoderFlavour' that maps the
name of the operation to the class that implements it. This way there
is only one selection point (converting the command line enum to the
appropriate DecodeFeatures object). In addition, there is no explicit
code replication: template instantiation hides that, and the compiler
should be able to resolve a number of things at compile-time.

isa,cpu: Add support for FS SMT Interrupts

Adds per-thread interrupt controllers and thread/context logic
so that interrupts properly get routed in SMT systems.

arm: Fix typo in ldrsh instruction name

ldrsh was typoed as hdrsh, which is a bit annoying when printing
instructions. This patch fixes it.

arm: Add missing FPEXC.EN check

Add a missing check to ensure that exceptions are generated properly.

arm: Fixes based on UBSan and static analysis

Another churn to clean up undefined behaviour, mostly ARM, but some
parts also touching the generic part of the code base.

Most of the fixes are simply ensuring that proper intialisation. One
of the more subtle changes is the return type of the sign-extension,
which is changed to uint64_t. This is to avoid shifting negative
values (undefined behaviour) in the ISA code.

arm: Don't speculatively access most miscregisters.

Speculative exeuction can cause panics in detailed execution mode that
shouldn't happen.

arch: Use shared_ptr for all Faults

This patch takes quite a large step in transitioning from the ad-hoc
RefCountingPtr to the c++11 shared_ptr by adopting its use for all
Faults. There are no changes in behaviour, and the code modifications
are mostly just replacing "new" with "make_shared".

arm: Fixed undefined behaviours identified by gcc

This patch fixes the runtime errors highlighted by the undefined
behaviour sanitizer. In the end there were two issues. First, when
rotating an immediate, we ended up shifting an uint32_t by 32 in some
cases. This case is fixed by checking for a rotation by 0
positions. Second, the Mrc15 and Mcr15 are operating on an IntReg and
a MiscReg, but we used the type RegRegImmOp and passed a MiscRegIndex
as an IntRegIndex. This issue is resolved by introducing a
MiscRegRegImmOp and RegMiscRegImmOp with the appropriate types.

With these fixes there are no runtime errors identified for the full
ARM regressions.

arm: Make memory ops work on 64bit/128-bit quantities

Multiple instructions assume only 32-bit load operations are available,
this patch increases load sizes to 64-bit or 128-bit for many load pair and
load multiple instructions.

arm: Fix v8 neon latency issue for loads/stores

Neon memory ops that operate on multiple registers currently have very poor
performance because of interleave/deinterleave micro-ops.

This patch marks the deinterleave/interleave micro-ops as "No_OpClass" such
that they take minumum cycles to execute and are never resource constrained.

Additionaly the micro-ops over-read registers. Although one form may need
to read up to 20 sources, not all do. This adds in new forms so false
dependencies are not modeled. Instructions read their minimum number of
sources.

arm: Mark v7 cbz instructions as direct branches

v7 cbz/cbnz instructions were improperly marked as indirect branches.

arm: Make sure UndefinedInstructions are properly initialized

arm: add preliminary ISA splits for ARM arch

arm: Panics in miscreg read functions can be tripped by O3 model

Unimplemented miscregs for the generic timer were guarded by panics
in arm/isa.cc which can be tripped by the O3 model if it speculatively
executes a wrong path containing a mrs instruction with a bad miscreg
index. These registers were flagged as implemented and accessible.
This patch changes the miscreg info bit vector to flag them as
unimplemented and inaccessible. In this case, and UndefinedInst
fault will be generated if the register access is not trapped
by a hypervisor.

arm: cleanup ARM ISA definition

arm: m5ops readfile64 args broken, offset coming through garbage

There were several sections of the m5ops code which were
essentially copy/pasted versions of the 32-bit code. The
problem is that some of these didn't account fo4 64-bit
registers leading to arguments being in the wrong registers.
This patch addresses the args for readfile64, writefile64,
and addsymbol64 -- all of which seemed to suffer from a
similar set of problems when moving to 64-bit.

arm: Add support for ARMv8 (AArch64 & AArch32)

Note: AArch64 and AArch32 interworking is not supported. If you use an AArch64
kernel you are restricted to AArch64 user-mode binaries. This will be addressed
in a later patch.

Note: Virtualization is only supported in AArch32 mode. This will also be fixed
in a later patch.

Contributors:
Giacomo Gabrielli (TrustZone, LPAE, system-level AArch64, AArch64 NEON, validation)
Thomas Grocutt (AArch32 Virtualization, AArch64 FP, validation)
Mbou Eyole (AArch64 NEON, validation)
Ali Saidi (AArch64 Linux support, code integration, validation)
Edmund Grimley-Evans (AArch64 FP)
William Wang (AArch64 Linux support)
Rene De Jong (AArch64 Linux support, performance opt.)
Matt Horsnell (AArch64 MP, validation)
Matt Evans (device models, code integration, validation)
Chris Adeniyi-Jones (AArch64 syscall-emulation)
Prakash Ramrakhyani (validation)
Dam Sunwoo (validation)
Chander Sudanthi (validation)
Stephan Diestelhorst (validation)
Andreas Hansson (code integration, performance opt.)
Eric Van Hensbergen (performance opt.)
Gabe Black

arm: Add support for the m5fail pseudo-op

scons: Fix warnings issued by clang 3.2svn (XCode 4.6)

This patch fixes the warnings that clang3.2svn emit due to the "-Wall"
flag. There is one case of an uninitialised value in the ARM neon ISA
description, and then a whole range of unused private fields that are
pruned.

scons: Add warning for missing declarations

This patch enables warnings for missing declarations. To avoid issues
with SWIG-generated code, the warning is only applied to non-SWIG
code.

arm: fix some fp comparisons that worked by accident.

The explict tests in the follwing fp comparison operations were
incorrect as they checked for only signaling NaNs and not quite-NaNs
as well. When compiled with gcc, the comparison generates a fp exception
that causes the FE_INVALID flag to be set and we check for it, so even
though the check was incorrect, the correct exception was set. With clang
this behavior seems to not occur. The checks are updated to test for nans and
the behavior is now correct with both clang and gcc.

ARM: Predict target of more instructions that modify PC.

ARM: Fix identification of one RAS pop instruction.

The check should be with the op2 field, not with the op1 field.

ARM: IT doesn't need to be serializing.

ARM: Add limited CP14 support.

New kernels attempt to read CP14 what debug architecture is available.
These changes add the debug registers and return that none is currently
available.

Merge with head, hopefully the last time for this batch.

Merge yet again with the main repository.

Merge with the main repository again.

Merge with main repository.

SE/FS: Get rid of FULL_SYSTEM in the ARM ISA.

util: implements "writefile" gem5 op to export file from guest to host filesystem

Usage: m5 writefile <filename>

File will be created in the gem5 output folder with the identical filename.
Implementation is largely based on the existing "readfile" functionality.
Currently does not support exporting of folders.

CheckerCPU: Re-factor CheckerCPU to be compatible with current gem5

Brings the CheckerCPU back to life to allow FS and SE checking of the
O3CPU. These changes have only been tested with the ARM ISA. Other
ISAs potentially require modification.

ARM: Add support for initparam m5 op

ARM: Add IsSerializeAfter and IsNonSpeculative flag to the syscall instruction .

Squashes the subsequent instructions in O3 pipe after the service call, so that
they see the effect of the system call when re-executed. This isn't really an issue
with FS mode, but can show up in SE mode.

GCC: Get everything working with gcc 4.6.1.

And by "everything" I mean all the quick regressions.

ISA parser: Use '_' instead of '.' to delimit type modifiers on operands.

By using an underscore, the "." is still available and can unambiguously be
used to refer to members of a structure if an operand is a structure, class,
etc. This change mostly just replaces the appropriate "."s with "_"s, but
there were also a few places where the ISA descriptions where handling the
extensions themselves and had their own regular expressions to update. The
regular expressions in the isa parser were updated as well. It also now
looks for one of the defined type extensions specifically after connecting "_"
where before it would look for any sequence of characters after a "."
following an operand name and try to use it as the extension. This helps to
disambiguate cases where a "_" may legitimately be part of an operand name but
not separate the name from the type suffix.

Because leaving the "_" and suffix on the variable name still leaves a valid
C++ identifier and all extensions need to be consistent in a given context, I
considered leaving them on as a breadcrumb that would show what the intended
type was for that operand. Unfortunately the operands can be referred to in
code templates, the Mem operand in particular, and since the exact type of Mem
can be different for different uses of the same template, that broke things.

Pseudoinst: Add an initParam pseudo inst function.

Fix bugs due to interaction between SEV instructions and O3 pipeline

SEV instructions were originally implemented to cause asynchronous squashes
via the generateTCSquash() function in the O3 pipeline when updating the
SEV_MAILBOX miscReg. This caused race conditions between CPUs in an MP system
that would lead to a pipeline either going inactive indefinitely or not being
able to commit squashed instructions. Fixed SEV instructions to behave like
interrupts and cause synchronous sqaushes inside the pipeline, eliminating
the race conditions. Also fixed up the semantics of the WFE instruction to
behave as documented in the ARMv7 ISA description to not sleep if SEV_MAILBOX=1
or unmasked interrupts are pending.

ARM: Fix SWP/SWPB undefined instruction behavior

SWP and SWPB now throw an undefined instruction exception if
SCTLR.SW == 0. This also required the MIDR to be changed
slightly so programs can correctly determine that gem5 supports
the ARM v7 behavior of SWP/SWPB (in ARM v6, SWP/SWPB were
deprecated, but not disabled at CPU startup).

ARM: Add m5ops and related support for workbegin() and workend() to ARM ISA.

gcc: fix an uninitialized variable warning from G++ 4.5

ARM: Generate condition code setting code based on which codes are set.

This change further eliminates cases where condition codes were being read
just so they could be written without change because the instruction in
question was supposed to preserve them. This is done by creating the condition
code code based on the input rather than just doing a simple substitution.

ARM: Construct the predicate test register for more instruction programatically.

If one of the condition codes isn't being used in the execution we should only
read it if the instruction might be dependent on it. With the preeceding changes
there are several more cases where we should dynamically pick instead of assuming
as we did before.

ARM: Further break up condition code into NZ, C, V bits.

Break up the condition code bits into NZ, C, V registers. These are individually
written and this removes some incorrect dependencies between instructions.

ARM: Remove the saturating (Q) condition code from the renamed register.

Move the saturating bit (which is also saturating) from the renamed register
that holds the flags to the CPSR miscreg and adds a allows setting it in a
similar way to the FP saturating registers. This removes a dependency in
instructions that don't write, but need to preserve the Q bit.

ARM: Break up condition codes into normal flags, saturation, and simd.

This change splits out the condcodes from being one monolithic register
into three blocks that are updated independently. This allows CPUs
to not have to do RMW operations on the flags registers for instructions
that don't write all flags.

ARM: Implement WFE/WFI/SEV semantics.

ARM: Use CPU local lock before sending load to mem system.

This change uses the locked_mem.hh header to handle implementing CLREX. It
simplifies the current implementation greatly.

ARM: Cleanup and small fixes to some NEON ops to match the spec.

Only certain bits of the cpacr can be written, some must be equal.
Mult instructions that write the same register should do something sane

ARM: Cleanup implementation of ITSTATE and put important code in PCState.

Consolidate all code to handle ITSTATE in the PCState object rather than
touching a variety of structures/objects.

ARM: Fix m5op parameters bug.

All the m5op parameters are 64 bits, but we were only sending 32 bits;
and the static register indexes were incorrectly specified.

ARM: Tag appropriate instructions as IsReturn

ARM: Fix subtle bug in LDM.

If the instruction faults mid-op the base register shouldn't be written back.

ARM: Identify branches as conditional or unconditional and direct or indirect.

ARM: Allow conditional quiesce instructions.

This patch prevents not executed conditional instructions marked as
IsQuiesce from stalling the pipeline indefinitely. If the instruction
is not executed the quiesceSkip psuedoinst is called which schedules a
wakes up call to the fetch stage.

ARM: Fix RFE macrop.

This changes the RFE macroop into 3 microops:

URa = [sp]; URb = [sp+4]; // load CPSR,PC values from stack
sp = sp + offset; // optionally auto-increment
PC = URa; CPSR = URb; // write to the PC and CPSR.

Importantly:
- writing to PC is handled in the last micro-op.
- loading occurs prior to state changes.

ARM: Rename registers used as temporary state by microops.

ARM: Previous change didn't end up setting instFlags, this does.

ARM: Squash state on FPSCR stride or len write.

ARM: Mark store conditionals as such.

ARM: Do something for ISB, DSB, DMB

ARM: Make Noop actually decode to a noop and set it's instflags.

O3: Fix itstate prediction and recovery.

Any change of control flow now resets the itstate to 0 mask and 0 condition,
except where the control flow alteration write into the cpsr register. These
case, for example return from an iterrupt, require the predecoder to recover
the itstate.

As there is a window of opportunity between the return from an interrupt
changing the control flow at the head of the pipe and the commit of the update
to the CPSR, the predecoder needs to be able to grab the ITstate early. This
is now handled by setting the forcedItState inside a PCstate for the control
flow altering instruction.

That instruction will have the correct mask/cond, but will not have a valid
itstate until advancePC is called (note this happens to advance the execution).
When the new PCstate is copy constructed it gets the itstate cond/mask, and
upon advancing the PC the itstate becomes valid.

Subsequent advancing invalidates the state and zeroes the cond/mask. This is
handled in isolation for the ARM ISA and should have no impact on other ISAs.

Refer arch/arm/types.hh and arch/arm/predecoder.cc for the details.

ARM: The ARM decoder should not panic when decoding undefined holes is arch.

This can abort simulations when the fetch unit runs ahead and speculatively
decodes instructions that are off the execution path.

ARM: Add support for moving predicated false dest operands from sources.

ARM: Take advantage of new PCState syntax.

O3: Make all instructions that write a misc. register not perform the write until commit.

ARM instructions updating cumulative flags (ARM FP exceptions and saturation
flags) are not serialized.

Added aliases for ARM FP exceptions and saturation flags in FPSCR. Removed
write accesses to the FP condition codes for most ARM VFP instructions: only
VCMP and VCMPE instructions update the FP condition codes. Removed a potential
cause of seg. faults in the O3 model for NEON memory macro-ops (ARM).

O3: Support SWAP and predicated loads/store in ARM.

CPU/ARM: Add SIMD op classes to CPU models and ARM ISA.

ARM: Fix SRS instruction to micro-code memory operation and register update.

Previously the SRS instruction attempted to writeback in initiateAcc() which
worked until a recent change, but was incorrect.

ARM: Add support for M5 ops in the ARM ISA

ARM/Alpha/Cpu: Change prefetchs to be more like normal loads.

This change modifies the way prefetches work. They are now like normal loads
that don't writeback a register. Previously prefetches were supposed to call
prefetch() on the exection context, so they executed with execute() methods
instead of initiateAcc() completeAcc(). The prefetch() methods for all the CPUs
are blank, meaning that they get executed, but don't actually do anything.

On Alpha dead cache copy code was removed and prefetches are now normal ops.
They count as executed operations, but still don't do anything and IsMemRef is
not longer set on them.

On ARM IsDataPrefetch or IsInstructionPreftech is now set on all prefetch
instructions. The timing simple CPU doesn't try to do anything special for
prefetches now and they execute with the normal memory code path.

ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors.



This change is a low level and pervasive reorganization of how PCs are managed
in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about,
the PC and the NPC, and the lsb of the PC signaled whether or not you were in
PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next
micropc, x86 and ARM introduced variable length instruction sets, and ARM
started to keep track of mode bits in the PC. Each CPU model handled PCs in
its own custom way that needed to be updated individually to handle the new
dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack,
the complexity could be hidden in the ISA at the ISA implementation's expense.
Areas like the branch predictor hadn't been updated to handle branch delay
slots or micropcs, and it turns out that had introduced a significant (10s of
percent) performance bug in SPARC and to a lesser extend MIPS. Rather than
perpetuate the problem by reworking O3 again to handle the PC features needed
by x86, this change was introduced to rework PC handling in a more modular,
transparent, and hopefully efficient way.


PC type:

Rather than having the superset of all possible elements of PC state declared
in each of the CPU models, each ISA defines its own PCState type which has
exactly the elements it needs. A cross product of canned PCState classes are
defined in the new "generic" ISA directory for ISAs with/without delay slots
and microcode. These are either typedef-ed or subclassed by each ISA. To read
or write this structure through a *Context, you use the new pcState() accessor
which reads or writes depending on whether it has an argument. If you just
want the address of the current or next instruction or the current micro PC,
you can get those through read-only accessors on either the PCState type or
the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the
move away from readPC. That name is ambiguous since it's not clear whether or
not it should be the actual address to fetch from, or if it should have extra
bits in it like the PAL mode bit. Each class is free to define its own
functions to get at whatever values it needs however it needs to to be used in
ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the
PC and into a separate field like ARM.

These types can be reset to a particular pc (where npc = pc +
sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as
appropriate), printed, serialized, and compared. There is a branching()
function which encapsulates code in the CPU models that checked if an
instruction branched or not. Exactly what that means in the context of branch
delay slots which can skip an instruction when not taken is ambiguous, and
ideally this function and its uses can be eliminated. PCStates also generally
know how to advance themselves in various ways depending on if they point at
an instruction, a microop, or the last microop of a macroop. More on that
later.

Ideally, accessing all the PCs at once when setting them will improve
performance of M5 even though more data needs to be moved around. This is
because often all the PCs need to be manipulated together, and by getting them
all at once you avoid multiple function calls. Also, the PCs of a particular
thread will have spatial locality in the cache. Previously they were grouped
by element in arrays which spread out accesses.


Advancing the PC:

The PCs were previously managed entirely by the CPU which had to know about PC
semantics, try to figure out which dimension to increment the PC in, what to
set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction
with the PC type itself. Because most of the information about how to
increment the PC (mainly what type of instruction it refers to) is contained
in the instruction object, a new advancePC virtual function was added to the
StaticInst class. Subclasses provide an implementation that moves around the
right element of the PC with a minimal amount of decision making. In ISAs like
Alpha, the instructions always simply assign NPC to PC without having to worry
about micropcs, nnpcs, etc. The added cost of a virtual function call should
be outweighed by not having to figure out as much about what to do with the
PCs and mucking around with the extra elements.

One drawback of making the StaticInsts advance the PC is that you have to
actually have one to advance the PC. This would, superficially, seem to
require decoding an instruction before fetch could advance. This is, as far as
I can tell, realistic. fetch would advance through memory addresses, not PCs,
perhaps predicting new memory addresses using existing ones. More
sophisticated decisions about control flow would be made later on, after the
instruction was decoded, and handed back to fetch. If branching needs to
happen, some amount of decoding needs to happen to see that it's a branch,
what the target is, etc. This could get a little more complicated if that gets
done by the predecoder, but I'm choosing to ignore that for now.


Variable length instructions:

To handle variable length instructions in x86 and ARM, the predecoder now
takes in the current PC by reference to the getExtMachInst function. It can
modify the PC however it needs to (by setting NPC to be the PC + instruction
length, for instance). This could be improved since the CPU doesn't know if
the PC was modified and always has to write it back.


ISA parser:

To support the new API, all PC related operand types were removed from the
parser and replaced with a PCState type. There are two warts on this
implementation. First, as with all the other operand types, the PCState still
has to have a valid operand type even though it doesn't use it. Second, using
syntax like PCS.npc(target) doesn't work for two reasons, this looks like the
syntax for operand type overriding, and the parser can't figure out if you're
reading or writing. Instructions that use the PCS operand (which I've
consistently called it) need to first read it into a local variable,
manipulate it, and then write it back out.


Return address stack:

The return address stack needed a little extra help because, in the presence
of branch delay slots, it has to merge together elements of the return PC and
the call PC. To handle that, a buildRetPC utility function was added. There
are basically only two versions in all the ISAs, but it didn't seem short
enough to put into the generic ISA directory. Also, the branch predictor code
in O3 and InOrder were adjusted so that they always store the PC of the actual
call instruction in the RAS, not the next PC. If the call instruction is a
microop, the next PC refers to the next microop in the same macroop which is
probably not desirable. The buildRetPC function advances the PC intelligently
to the next macroop (in an ISA specific way) so that that case works.


Change in stats:

There were no change in stats except in MIPS and SPARC in the O3 model. MIPS
runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could
likely be improved further by setting call/return instruction flags and taking
advantage of the RAS.


TODO:

Add != operators to the PCState classes, defined trivially to be !(a==b).
Smooth out places where PCs are split apart, passed around, and put back
together later. I think this might happen in SPARC's fault code. Add ISA
specific constructors that allow setting PC elements without calling a bunch
of accessors. Try to eliminate the need for the branching() function. Factor
out Alpha's PAL mode pc bit into a separate flag field, and eliminate places
where it's blindly masked out or tested in the PC.

Mem: Change the CLREX flag to CLEAR_LL.

CLREX is the name of an ARM instruction, not a name for this generic flag.

ARM: Clean up use of TBit and JBit.

Rather tha constantly using ULL(1) << PcXBitShift define those directly.
Additionally, add some helper functions to further clean up the code.

ARM: Make VMSR, RFE PC/LR etc non speculative, and serializing

ARM: Use fewer micro-ops for register update loads if possible.

Allow some loads that update the base register to use just two micro-ops. three
micro-ops are only used if the destination register matches the offset register
or the PC is the destination regsiter. If the PC is updated it needs to be
the last micro-op otherwise O3 will mispredict.

ARM: Fix VFP enabled checks for mem instructions

ARM: Seperate out the renamable bits in the FPSCR.

ARM: Fix type comparison warnings in Neon.

ARM: Implement CPACR register and return Undefined Instruction when FP access is disabled.

ARM: Implement all ARM SIMD instructions.

ARM: Implement DBG instruction that doesn't do much for now.

MEM: Make CLREX a first class request operation and clear locks in caches when it in received

ARM: Implement CLREX init/complete acc methods

ARM: Implement DSB, DMB, ISB

ARM: Implement CLREX

ARM: BX instruction can be contitional if last instruction in a IT block

Branches are allowed to be the last instuction in an IT block. Before it was
assumed that they could not. So Branches in thumb2 were Uncond.

ARM: mark msr/mrs instructions as SerializeBefore/After
Since miscellaneous registers bypass wakeup logic, force serialization
to resolve data dependencies through them
* * *
ARM: adding non-speculative/serialize flags for instructions change CPSR

ARM: Temporary local variables can't conflict with isa parser operands.
PC is an operand, so we can't have a temp called PC

ARM: Exclusive accesses must be double word aligned

ARM: Clean up the ISA desc portion of the ARM memory instructions.

ARM: Decode to specialized conditional/unconditional versions of instructions.

This is to avoid condition code based dependences from effectively serializing
instructions when the instruction doesn't actually use them.

ARM: Implement a version of mcr and mrc that works in user mode.

ARM: Move some miscellaneous instructions out of the decoder to share with thumb.

ARM: Implement the bkpt instruction.

ARM: Make undefined instructions obey predication.

ARM: Implement support for the IT instruction and the ITSTATE bits of CPSR.

ARM: Implement the ARM TLB/Tablewalker. Needs performance improvements.

ARM: Implement ARM CPU interrupts

ARM: Implement conversion to/from half precision.

ARM: Clean up VFP

ARM: Clean up the implementation of the VFP instructions.

ARM: Implement the version of VMRS that writes to the APSR.

ARM: Implement the VCMPE instruction.

ARM: Fix vcvtr so that it uses the rounding mode in the FPSCR.

ARM: Fix saturation of VCVT from fp to integer.

ARM: Compensate for ARM's underflow coming from -before- rounding, but x86's after.

ARM: Implement flush to zero for destinations as well.

ARM: Fix up nans to match ARM's expected behavior.

ARM: Implement flush to zero mode for VFP, and clean up some corner cases.

ARM: Add barriers that make sure FP operations happen where they're supposed to.

ARM: Implement the version of VCVT float to int that rounds towards zero.

ARM: Implement the floating/fixed point VCVT instructions.

ARM: Add code to extract and record VFP exceptions.

ARM: Implement the VFP version of VCMP.

ARM: Add support for VFP vector mode.

ARM: Introduce new VFP base classes that are optionally microops.

ARM: Implement VCVT between double and single width FP.

ARM: Implement vcvt between int and fp. Ignore rounding.

ARM: Implement the VFP negated multiplies.

ARM: Implement the VFP versions of VMLA and VMLS.

ARM: Implement the VFP version of vdiv and vsqrt.

ARM: Implement the VFP version of vsub.

ARM: Implement the VFP version of vadd.

ARM: Implement the VFP version of vabs.

ARM: Implement the VFP version of vneg.

ARM: Implement the VFP version of vmul.

ARM: Make integer division by zero return a fault.

ARM: Undef instruction on invalid user CP15 access

ARM: Implement the vstr instruction.

ARM: Fix the implementation of the VFP ldm and stm macroops.

There were four bugs in these instructions. First, the loaded value was being
stored into a floating point register as floating point, changing the value as
it was transfered. Second, the meaning of the "up" bit had been reversed.
Third, the statically sized microop array wasn't bit enough for all possible
inputs. It's now dynamically sized and should always be big enough. Fourth,
the offset was stored as an unsigned 8 bit value. Negative offsets would look
like moderately large positive offsets.

ARM: Implement the VLDR instruction.

ARM: Implement the various versions of VMOV.

ARM: Implement the VMRS instruction.

ARM: Implement the VMSR instruction.

ARM: Implement the udiv instruction.

ARM: Implement the sdiv instruction.

ARM: Implement the CPS instruction.

ARM: Implement the SRS instruction.

ARM: Define the setend instruction.

ARM: Implement the strex instructions.

ARM: Respect the E bit of the CPSR when doing loads and stores.

ARM: Implement the V7 version of alignment checking.

ARM: Implement the RFE instruction.

ARM: Implement the enterx and leavex instructions.

These enter and leave thumbEE mode. Currently thumbEE mode behaves exactly the
same as Thumb mode, but at least this will make it -look- like we're enter and
leaving it. The actual behavioral changes will be implemented in future
changes.

ARM: Fix the implementation of BX to work in thumbEE mode.

ARM: Explicitly keep track of the second destination for double loads/stores.

ARM: Implement the mrc and mcr instructions.

ARM: Rename the RevOp base class to something more generic.

ARM: Implement the bfc and bfi instructions.

ARM: Implement the ubfx and sbfx instructions.

ARM: Decode the clz instruction.

ARM: Implement the clz instruction.

ARM: Implement the rbit instruction.

ARM: Implement nop.

ARM: Implement the ldrex instruction.

ARM: Implement the usad8 and usada8 instructions.

ARM: Implement the sel instruction.

ARM: Implement the pkh instruction.

ARM: Implement zero/sign extend instructions.

ARM: Generalize the saturation instruction bases for use in other instructions.

ARM: Implement the 8/16 bit signed/unsigned add/subtract half instructions.

ARM: Fix signed most significant multiply instructions.

ARM: Fix multiply overflow flag setting.

ARM: Implement the saturation instructions.

ARM: Implement signed add/subtract and subtract/add.

ARM: Implement the unsigned 8 bit and 16 bit vector adds and subtracts.

ARM: Implement the unsigned saturating instructions.

ARM: Implement the ssub instructions.

ARM: Implement the SADD8 and SADD16 instructions.