AArch64InstrInfo::optimizeCompareInstr has bug PR27158 which causes generation of incorrect code.
A compare instruction is substituted with another instruction which does not
produce the same flags as the original compare instruction.
This patch contains:
1. Fix of the bug.
2. A regression test in MIR.
3. A new test to check that SUBS is replaced by SUB.
Differential Revision: http://reviews.llvm.org/D18838
llvm-svn: 266969
CTTZ_ZERO_UNDEF can be custom lowered specially if CTLZ is supported. Otherwise CTTZ and CTTZ_ZERO_UNDEF are handled the same way by using CTPOP and bitmath.
llvm-svn: 266952
Differentiate between word and subword memory operations as they take different
amount of cycles to complete. This just adds a basic model of the subword
latency to the scheduler.
llvm-svn: 266898
Add ParseAMDGPURegister which can be invoked recursively for parsing lists.
Rename getRegForName to getSpecialRegForName.
Support legacy SP3 register list syntax: [s2,s3,s4,s5] or [flat_scratch_lo,flat_scratch_hi].
Add 64-bit registers TBA, TMA where missing.
Add some tests.
Differential Revision: http://reviews.llvm.org/D19163
llvm-svn: 266865
Because lowering of CMP_SWAP_64 occurs during type legalization, there can be
i64 types produced by more than just a BUILD_PAIR or similar. My initial tests
used just incoming function args.
llvm-svn: 266828
Summary:
This property is used to mark an intrinsic that only writes to memory, but
neither reads from memory nor has other side effects.
An example where this is useful is the llvm.amdgcn.buffer.store.format.*
intrinsic, which corresponds to a store instruction that goes through a special
buffer descriptor rather than through a plain pointer.
With this property, the intrinsic should still be handled as having side
effects at the LLVM IR level, but machine scheduling can make smarter
decisions.
Reviewers: tstellarAMD, arsenm, joker.eph, reames
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D18291
llvm-svn: 266826
Summary:
The added testcase, which triggered this, was derived from a shader-db case
via bugpoint. A separate question is why scalar branching wasn't used.
Reviewers: arsenm, tstellarAMD
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D19208
llvm-svn: 266825
Summary:
A shader stored the live mask (initial exec mask) in an SGPR which was then
spilled during register allocation. The allocator quite reasonably
optimized turned the spill into
v_writelane_b32 %vgpr, exec_lo, N
v_writelane_b32 %vgpr, exec_hi, N+1
at the beginning of the shader, confusing the SGPR accounting.
No test case, because si-sgpr-spill.ll together with an upcoming patch for
WQM handling exhibits the problem.
Reviewers: arsenm, tstellarAMD
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D19199
llvm-svn: 266824
Both AArch64 and ARM support llvm.<arch>.thread.pointer intrinsics that
just return the thread pointer. I have a pending patch that does the same
for SystemZ (D19054), and there are many more targets that could benefit
from one.
This patch merges the ARM and AArch64 intrinsics into a single target
independent one that will also be used by subsequent targets.
Differential Revision: http://reviews.llvm.org/D19098
llvm-svn: 266818
With this change, ideally IR pass can always generate llvm.stackguard
call to get the stack guard; but for now there are still IR form stack
guard customizations around (see getIRStackGuard()). Future SSP
customization should go through LOAD_STACK_GUARD.
There is a behavior change: stack guard values are not CSEed anymore,
since we should never reuse the value in case that it has been spilled (and
corrupted). See ssp-guard-spill.ll. This also cause the change of stack
size and codegen in X86 and AArch64 test cases.
Ideally we'd like to know if the guard created in llvm.stackprotector() gets
spilled or not. If the value is spilled, discard the value and reload
stack guard; otherwise reuse the value. This can be done by teaching
register allocator to know how to rematerialize LOAD_STACK_GUARD and
force a rematerialization (which seems hard), or check for spilling in
expandPostRAPseudo. It only makes sense when the stack guard is a global
variable, which requires more instructions to load. Anyway, this seems to go out
of the scope of the current patch.
llvm-svn: 266806
* Add lowering for SETCCE i32.
* Add test to check lowering of i64 compares uses SETCCE expansion (outside of EQ and NE).
* Fix select.ll test and immediate form selection for RI operations.
llvm-svn: 266802
in preparation for enabling the outgoing parameter store-to-push optimization
for 64-bit targets.
Differential Revision: http://reviews.llvm.org/D19222
llvm-svn: 266774
Using VPERMQ/VPERMPD allows memory folding of the (repeated) input where VINSERTI128/VINSERTF128 can not.
Differential Revision: http://reviews.llvm.org/D19228
llvm-svn: 266728
Summary:
The `"patchable-function"` attribute can be used by an LLVM client to
influence LLVM's code generation in ways that makes the generated code
easily patchable at runtime (for instance, to redirect control).
Right now only one patchability scheme is supported,
`"prologue-short-redirect"`, but this can be expanded in the future.
Reviewers: joker.eph, rnk, echristo, dberris
Subscribers: joker.eph, echristo, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D19046
llvm-svn: 266715
The fast register-allocator cannot cope with inter-block dependencies without
spilling. This is fine for ldrex/strex loops coming from atomicrmw instructions
where any value produced within a block is dead by the end, but not for
cmpxchg. So we lower a cmpxchg at -O0 via a pseudo-inst that gets expanded
after regalloc.
Fortunately this is at -O0 so we don't have to care about performance. This
simplifies the various axes of expansion considerably: we assume a strong
seq_cst operation and ensure ordering via the always-present DMB instructions
rather than v8 acquire/release instructions.
Should fix the 32-bit part of PR25526.
llvm-svn: 266679
There's currently no raw_ostream &operator<<(SimpleValueType); provided by LLVM. It could be added by refactoring utils/TableGen/CodeGenTarget.cpp:getEnumName, but that's much more work than fixing the build.
llvm-svn: 266627
