Summary:
This pass sinks COPY instructions into a successor block, if the COPY is not
used in the current block and the COPY is live-in to a single successor
(i.e., doesn't require the COPY to be duplicated). This avoids executing the
the copy on paths where their results aren't needed. This also exposes
additional opportunites for dead copy elimination and shrink wrapping.
These copies were either not handled by or are inserted after the MachineSink
pass. As an example of the former case, the MachineSink pass cannot sink
COPY instructions with allocatable source registers; for AArch64 these type
of copy instructions are frequently used to move function parameters (PhyReg)
into virtual registers in the entry block..
For the machine IR below, this pass will sink %w19 in the entry into its
successor (%bb.1) because %w19 is only live-in in %bb.1.
```
%bb.0:
%wzr = SUBSWri %w1, 1
%w19 = COPY %w0
Bcc 11, %bb.2
%bb.1:
Live Ins: %w19
BL @fun
%w0 = ADDWrr %w0, %w19
RET %w0
%bb.2:
%w0 = COPY %wzr
RET %w0
```
As we sink %w19 (CSR in AArch64) into %bb.1, the shrink-wrapping pass will be
able to see %bb.0 as a candidate.
With this change I observed 12% more shrink-wrapping candidate and 13% more dead copies deleted in spec2000/2006/2017 on AArch64.
Reviewers: qcolombet, MatzeB, thegameg, mcrosier, gberry, hfinkel, john.brawn, twoh, RKSimon, sebpop, kparzysz
Reviewed By: sebpop
Subscribers: evandro, sebpop, sfertile, aemerson, mgorny, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D41463
llvm-svn: 328237
As in SystemZ backend, correctly propagate node ids when inserting new
unselected nodes into the DAG during instruction Seleciton for X86
target.
Fixes PR36865.
Reviewers: jyknight, craig.topper
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D44797
llvm-svn: 328233
This fixes a few issues with the R52 instregexs to enable the full overlap checking
Differential Revision: https://reviews.llvm.org/D44767
llvm-svn: 328216
Models were completely overriding all CLMUL instructions when the WriteCLMUL default classes could be used for exactly the same coverage.
llvm-svn: 328194
PCLMULQDQrm was using the rr itinerary.
Difference in itineraries between PCLMULQDQ/VPCLMULQDQ variants was causing an unnecessary duplication of scheduler class entries.
llvm-svn: 328193
Models were completely overriding all AES instructions when the WriteAES default classes could be used for exactly the same coverage.
Removes 6 unnecessary scheduler classes from every model.
Note: Still looking for a way for tblgen to warn when this is happening - often the override is more complete than the default.
llvm-svn: 328192
I've also merged some VEX/non-VEX instregex strings with a (V?) prefix or (Y?) ymm variant - there are still a lot more of these to do.
This reduces the size of the optimized llc binary on my computer by 400K. Presumably because we went from 5000+ scheduler classes per CPU to ~2000.
llvm-svn: 328179
Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.
Transforms depends on Transforms/Utils, not the other way around. So
remove the header and the "createStripGCRelocatesPass" function
declaration (& definition) that is unused and motivated this dependency.
Move Transforms/Utils/Local.h into Analysis because it's used by
Analysis/MemoryBuiltins.cpp.
llvm-svn: 328165
This is needed for the upcoming implementation of the
new 8x32x16 and 32x8x16 variants of WMMA instructions
introduced in CUDA 9.1.
Differential Revision: https://reviews.llvm.org/D44719
llvm-svn: 328158
The "ShouldEmitMatchRegisterName" bit wasn't taking effect because the
WebAssembly target didn't point to the custom WebAssemblyAsmParser
record.
llvm-svn: 328155
Add barrier edges to check for any physical register. The previous code
worked for the function return registers: r0/d0, v0/w0.
Patch by Brendon Cahoon.
llvm-svn: 328120
I've also merged some VEX/non-VEX instregex strings with a (V?) prefix or (Y?) ymm variant - there are still a lot more of these to do.
llvm-svn: 328111
This patch also includes extensive tests targeted at select and br+fcmp IR
inputs. A sequence of br+fcmp required support for FPR32 registers to be added
to RISCVInstrInfo::storeRegToStackSlot and
RISCVInstrInfo::loadRegFromStackSlot.
llvm-svn: 328104
Also restrict to port 0 and 1 for SkylakeClient. It looks like the scheduler models don't account for client not having a full vector ALU on port 5 like server.
Fixes PR36808.
llvm-svn: 328061
The default thread model for wasm is single, and in this mode thread-local
global variables can be lowered identically to non-thread-local variables.
Differential Revision: https://reviews.llvm.org/D44703
llvm-svn: 328049
Mingw uses the same stack protector functions as GCC provides
on other platforms as well.
Patch by Valentin Churavy!
Differential Revision: https://reviews.llvm.org/D27296
llvm-svn: 328039
It uses the MC framework and the tablegen matcher to do the
heavy lifting. Can handle both explicit and implicit locals
(-disable-wasm-explicit-locals). Comes with a small regression
test.
This is a first basic implementation that can parse most llvm .s
output and round-trips most instructions succesfully, but in order
to keep the commit small, does not address all issues.
There are a fair number of mismatches between what MC / assembly
matcher think a "CPU" should look like and what WASM provides,
some already have workarounds in this commit (e.g. the way it
deals with register operands) and some that require further work.
Some of that further work may involve changing what the
Disassembler outputs (and what s2wasm parses), so are probably
best left to followups.
Some known things missing:
- Many directives are ignored and not emitted.
- Vararg calls are parsed but extra args not emitted.
- Loop signatures are likely incorrect.
- $drop= is not emitted.
- Disassembler does not output SIMD types correctly, so assembler
can't test them.
Patch by Wouter van Oortmerssen
Differential Revision: https://reviews.llvm.org/D44329
llvm-svn: 328028
I'm not entirely sure these hacks are still needed. If you remove the hacks completely, the name of the library call that gets generated doesn't match the grep the test previously had. So the test wasn't really checking anything.
If the hack is still needed it belongs in PPC specific code. I believe the FP_TO_SINT code here is the only place in the tree where a FP_ROUND_INREG node is created today. And I don't think its even being used correctly because the legalization returned a BUILD_PAIR with the same value twice. That doesn't seem right to me. By moving the code entirely to PPC we can avoid creating the FP_ROUND_INREG at all.
I replaced the grep in the existing test with full checks generated by hacking update_llc_test_check.py to support ppc32 just long enough to generate it.
Differential Revision: https://reviews.llvm.org/D44061
llvm-svn: 328017
Registers E[A-D]X, E[SD]I, E[BS]P, and EIP have 16-bit subregisters
that cover the low halves of these registers. This change adds artificial
subregisters for the high halves in order to differentiate (in terms of
register units) between the 32- and the low 16-bit registers.
This patch contains parts that aim to preserve the calculated register
pressure. This is in order to preserve the current codegen (minimize the
impact of this patch). The approach of having artificial subregisters
could be used to fix PR23423, but the pressure calculation would need
to be changed.
Differential Revision: https://reviews.llvm.org/D43353
llvm-svn: 328016
This way we can support address-space specific variants without explicitly
encoding the space in the name of the intrinsic. Less intrinsics to deal with ->
less boilerplate.
Added a bit of tablegen magic to match/replace an intrinsics with a pointer
argument in particular address space with the space-specific instruction
variant.
Updated tests to use non-default address spaces.
Differential Revision: https://reviews.llvm.org/D43268
llvm-svn: 328006
TopReadyCycle and BotReadyCycle were off by one cycle when an SU is either
the first instruction or the last instruction in a packet.
Patch by Ikhlas Ajbar.
llvm-svn: 328000
This patch changes the isLatencyBound heuristic to look at the
path length based upon the number of packets needed to schedule
a basic block. For small basic blocks, the heuristic uses a small
threshold for isLatencyBound. For large basic blocks, the
heuristic uses a large threshold.
The goal is to increase the priority of an instruction in a small
basic block that has a large height or depth relative to the code
size. For large functions, the height and depth are ignored
because it increases the live range of a register and causes more
spills. That is, for large functions, it is more important to
schedule instructions when available, and attempt to keep the defs
and uses closer together.
Patch by Brendon Cahoon.
llvm-svn: 327987
In these cases, both parameters and return values are passed
as a pointer to a stack allocation.
MSVC doesn't use the f80 data type at all, while it is used
for long doubles on mingw.
Normally, this part of the calling convention is handled
within clang, but for intrinsics that are lowered to libcalls,
it may need to be handled within llvm as well.
Differential Revision: https://reviews.llvm.org/D44592
llvm-svn: 327957
They were incorrectly marked as RMW operations. Some of the CMP instrucions worked, but the ones that use a similar encoding as RMW form of ADD ended up marked as RMW.
TEST used the same tablegen class as some of the CMPs.
llvm-svn: 327947
Jun Bum Lim