Summary:
This patch implements a tablegen-driven Instruction Compression
mechanism for generating RISCV compressed instructions
(C Extension) from the expanded instruction form.
This tablegen backend processes CompressPat declarations in a
td file and generates all the compile-time and runtime checks
required to validate the declarations, validate the input
operands and generate correct instructions.
The checks include validating register operands, immediate
operands, fixed register operands and fixed immediate operands.
Example:
class CompressPat<dag input, dag output> {
dag Input = input;
dag Output = output;
list<Predicate> Predicates = [];
}
let Predicates = [HasStdExtC] in {
def : CompressPat<(ADD GPRNoX0:$rs1, GPRNoX0:$rs1, GPRNoX0:$rs2),
(C_ADD GPRNoX0:$rs1, GPRNoX0:$rs2)>;
}
The result is an auto-generated header file
'RISCVGenCompressEmitter.inc' which exports two functions for
compressing/uncompressing MCInst instructions, plus
some helper functions:
bool compressInst(MCInst& OutInst, const MCInst &MI,
const MCSubtargetInfo &STI,
MCContext &Context);
bool uncompressInst(MCInst& OutInst, const MCInst &MI,
const MCRegisterInfo &MRI,
const MCSubtargetInfo &STI);
The clients that include this auto-generated header file and
invoke these functions can compress an instruction before emitting
it, in the target-specific ASM or ELF streamer, or can uncompress
an instruction before printing it, when the expanded instruction
format aliases is favored.
The following clients were added to implement compression\uncompression
for RISCV:
1) RISCVAsmParser::MatchAndEmitInstruction:
Inserted a call to compressInst() to compresses instructions
parsed by llvm-mc coming from an ASM input.
2) RISCVAsmPrinter::EmitInstruction:
Inserted a call to compressInst() to compress instructions that
were lowered from Machine Instructions (MachineInstr).
3) RVInstPrinter::printInst:
Inserted a call to uncompressInst() to print the expanded
version of the instruction instead of the compressed one (e.g,
add s0, s0, a5 instead of c.add s0, a5) when -riscv-no-aliases
is not passed.
This patch squashes D45119, D42780 and D41932. It was reviewed in smaller patches by
asb, efriedma, apazos and mgrang.
Reviewers: asb, efriedma, apazos, llvm-commits, sabuasal
Reviewed By: sabuasal
Subscribers: mgorny, eraman, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, niosHD, kito-cheng, shiva0217, zzheng
Differential Revision: https://reviews.llvm.org/D45385
llvm-svn: 329455
Summary:
The 'strong' StackProtector heuristic takes into consideration call instructions.
Certain intrinsics, such as lifetime.start, can cause the
StackProtector to protect functions that do not need to be protected.
Specifically, a volatile variable, (not optimized away), but belonging to a stack
allocation will encourage a llvm.lifetime.start to be inserted during
compilation. Because that intrinsic is a 'call' the strong StackProtector
will see that the alloca'd variable is being passed to a call instruction, and
insert a stack protector. In this case the intrinsic isn't really lowered to a
call. This can cause unnecessary stack checking, at the cost of additional
(wasted) CPU cycles.
In the future we should rely on TargetTransformInfo::isLoweredToCall, but as of
now that routine considers all intrinsics as not being lowerable. That needs
to be corrected, and such a change is on my list of things to get moving on.
As a side note, the updated stack-protector-dbginfo.ll test always seems to
pass. I never see the dbg.declare/dbg.value reaching the
StackProtector::HasAddressTaken, but I don't see any code excluding dbg
intrinsic calls either, so I think it's the safest thing to do.
Reviewers: void, timshen
Reviewed By: timshen
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45331
llvm-svn: 329450
Summary:
This patch updates MC tests related to compression in RISCV to
insure they work correctly with automatic compression and relaxation
enabled. This is the first part of a series of patches to implement
automatic compression for RISCV.
Reviewers: asb, apazos
Reviewed By: asb
Subscribers: shiva0217, efriedma, llvm-commits, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, niosHD, kito-cheng
Differential Revision: https://reviews.llvm.org/D43328
llvm-svn: 329441
Summary:
This patch removes InstRW overrides for basic arithmetic/logic instructions. To do this I've added the store address port to RMW. And used a WriteSequence to make the latency additive. It does not cover ADC/SBB because they have different latency.
Apparently we were inconsistent about whether the store has latency or not thus the test changes.
I've also left out Sandy Bridge because the load latency there is currently 4 cycles and should be 5.
Reviewers: RKSimon, andreadb
Reviewed By: andreadb
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45351
llvm-svn: 329416
D45344 is proposing to remove the use restriction that made the calloc
transform safe, but it doesn't currently address the problematic example
given inD16337. Add a test to make sure that doesn't break.
llvm-svn: 329412
Summary:
Fixing an issue where initializations of globals where constructors use
casts were silently translated to 0-initialization.
Reviewers: davidxl, evgeny777
Reviewed By: evgeny777
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45198
llvm-svn: 329409
Summary:
This patch add checks to verify that the information in the name index
entries is consistent with the debug_info section. Specifically, we
check that entries point to valid DIEs, and their names, tags, and
compile units match the information in the debug_info sections.
These checks are only run if the previous checks did not find any errors
in the name index headers. Attempting to proceed with the checks anyway
would likely produce a lot of spurious errors and the verification code
would need to be very careful to avoid crashing.
I also add a couple of more checks to the abbreviation-validation code
to verify that some attributes are always present (an index without a
DW_IDX_die_offset attribute is fairly useless).
The entry verification works only on indexes without any type units - I
haven't attempted to extend it to type units, as we don't even have a
DWARF v5-compatible type unit generator at the moment.
Reviewers: JDevlieghere, aprantl, dblaikie
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45323
llvm-svn: 329392
The script allows the auto-generation of checks for cost model tests to speed up their creation and help improve coverage, which will help a lot with PR36550.
If the need arises we can add support for other analyze passes as well, but the cost models was the one I needed to get done - at the moment it just warns that any other analysis mode is unsupported.
I've regenerated a couple of x86 test files to show the effect.
Differential Revision: https://reviews.llvm.org/D45272
llvm-svn: 329390
As mentioned on D44647, this patch increases the default memory latency to +5cy , which more closely matches what most custom cases are doing for reg-mem instructions.
I've bumped LoadLatency, ReadAfterLd and WriteLoad values to 5cy to be consistent.
As Sandy Bridge is currently our default generic model, this affects a lot of scheduling tests...
Differential Revision: https://reviews.llvm.org/D44654
llvm-svn: 329388
Inserting instrumentation between a musttail call and ret instruction
would create invalid IR. Instead, treat musttail calls as function
exits.
llvm-svn: 329385
MFI.LocalFrameSize was not serialized.
It is usually set from LocalStackSlotAllocation, so if that pass doesn't
run it is impossible do deduce it from the stack objects. Until now, this
information was lost.
llvm-svn: 329382
Summary:
The positions of the DwarfVersion and AddressSize arguments were
reversed, which caused parsing for dwarf opcodes which contained
address-size-dependent operands (such as DW_OP_addr). Amusingly enough,
none of the address-size asserts fired, as dwarf version was always 4,
which is a valid address size.
I ran into this when constructing weird inputs for the DWARF verifier. I
I add a test case as hand-written dwarf -- I am not sure how to trigger
this differently, as having a DW_OP_addr inside a location list is a
fairly non-standard thing to do.
Fixing this error exposed a bug in the debug_loc.dwo parser, which was
always being constructed with an address size of 0. I fix that as well
by following the pattern in the non-dwo parser of picking up the address
size from the first compile unit (which is technically not correct, but
probably good enough in practice).
Reviewers: JDevlieghere, aprantl, dblaikie
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45324
llvm-svn: 329381
VSX D-form load/store instructions of POWER9 require the offset be a multiple of 16 and a helper`isOffsetMultipleOf` is used to check this.
So far, the helper handles FrameIndex + offset case, but not handling FrameIndex without offset case. Due to this, we are missing opportunities to exploit D-form instructions when accessing an object or array allocated on stack.
For example, x-form store (stxvx) is used for int a[4] = {0}; instead of d-form store (stxv). For larger arrays, D-form instruction is not used when accessing the first 16-byte. Using D-form instructions reduces register pressure as well as instructions.
Differential Revision: https://reviews.llvm.org/D45079
llvm-svn: 329377
Summary:
- Add a missing getter for module-level inline assembly
- Add a missing append function for module-level inline assembly
- Deprecate LLVMSetModuleInlineAsm and replace it with LLVMSetModuleInlineAsm2 which takes an explicit length parameter
- Deprecate LLVMConstInlineAsm and replace it with LLVMGetInlineAsm, a function that allows passing a dialect and is not mis-classified as a constant operation
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45346
llvm-svn: 329369
This restores what was lost with rL73243 but without
re-introducing the bug that was present in the old code.
Note that we already have these transforms if the ops are
marked 'fast' (and I assume that's happening somewhere in
the code added with rL170471), but we clearly don't need
all of 'fast' for these transforms.
llvm-svn: 329362
A fold for this pattern was removed at rL73243 to fix PR4374:
https://bugs.llvm.org/show_bug.cgi?id=4374
...and apparently there were no tests that went with that fold.
llvm-svn: 329360
Summary:
More tests for D45108:
* One use tests
* allow shift to be a variable, too
Reviewers: spatel, craig.topper
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45329
llvm-svn: 329348
This is the 32-bit mode version of LEAVE64. It should be at least somewhat similar to LEAVE64.
The Sandy Bridge version was missing a load port use.
llvm-svn: 329347
Currently it is 6. If the "feature" was not used, report dummy
hidden argument. Otherwise it does not match the kernarg size
reported in the kernel header.
Differential Revision: https://reviews.llvm.org/D45129
llvm-svn: 329341
Sameer AbuAsal