Sanjay Patel e6b6787d01 [InstCombine] fold abs(X)/X to cmp+select ...

The backend can convert the select-of-constants to
bit-hack shift+logic if desirable.

https://alive2.llvm.org/ce/z/pgJT6E

  define i8 @src(i8 %x) {
  %0:
    %a = abs i8 %x, 1
    %d = sdiv i8 %x, %a
    ret i8 %d
  }
  =>
  define i8 @tgt(i8 %x) {
  %0:
    %cond = icmp sgt i8 %x, 255
    %r = select i1 %cond, i8 1, i8 255
    ret i8 %r
  }
  Transformation seems to be correct!

2020-08-17 08:01:28 -04:00

..

CMakeLists.txt

[InstCombine] Move target-specific inst combining

2020-07-22 15:59:49 +02:00

InstCombineAddSub.cpp

[InstCombine] Move target-specific inst combining

2020-07-22 15:59:49 +02:00

InstCombineAndOrXor.cpp

[InstCombine] ~(~X + Y) -> X - Y

2020-08-11 11:05:42 +02:00

InstCombineAtomicRMW.cpp

[InstCombine] Move target-specific inst combining

2020-07-22 15:59:49 +02:00

InstCombineCalls.cpp

[InstCombine] fold copysign with fabs/fneg operand

2020-08-16 08:53:47 -04:00

InstCombineCasts.cpp

[InstCombine] eliminate a pointer cast around insertelement

2020-08-12 09:08:17 -04:00

InstCombineCompares.cpp

[NFC][InstCombine] Refactor '(-NSW x) pred x' fold

2020-08-06 11:50:36 +03:00

InstCombineInternal.h

[InstCombine] Aggregate reconstruction simplification (PR47060)

2020-08-16 23:27:56 +03:00

InstCombineLoadStoreAlloca.cpp

[InstCombine] Move target-specific inst combining

2020-07-22 15:59:49 +02:00

InstCombineMulDivRem.cpp

[InstCombine] fold abs(X)/X to cmp+select

2020-08-17 08:01:28 -04:00

InstCombineNegator.cpp

[NFC][InstCombine] Negator: add a comment about negating exact arithmentic shift

2020-08-06 23:37:16 +03:00

InstCombinePHI.cpp

[InstCombine] Move target-specific inst combining

2020-07-22 15:59:49 +02:00

InstCombineSelect.cpp

[InstCombine] Use CreateVectorSplat(ElementCount) variant directly

2020-08-08 19:26:02 +01:00

InstCombineShifts.cpp

[InstCombine] Move target-specific inst combining

2020-07-22 15:59:49 +02:00

InstCombineSimplifyDemanded.cpp

[InstCombine] prefer xor with -1 because 'not' is easier to understand (PR32706)

2020-08-12 15:50:33 -04:00

InstCombineVectorOps.cpp

[InstCombine] Fix a compilation bug

2020-08-16 21:56:42 -07:00

InstructionCombining.cpp

[InstCombine] Aggregate reconstruction simplification (PR47060)

2020-08-16 23:27:56 +03:00

LLVMBuild.txt

Update the file headers across all of the LLVM projects in the monorepo

2019-01-19 08:50:56 +00:00