llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-01-12 17:32:19 +00:00

History

Evan Cheng bbbe413846 Remove a instcombine transform that (no longer?) makes sense:

// C - zext(bool) -> bool ? C - 1 : C
    if (ZExtInst *ZI = dyn_cast<ZExtInst>(Op1))
      if (ZI->getSrcTy()->isIntegerTy(1))
        return SelectInst::Create(ZI->getOperand(0), SubOne(C), C);

This ends up forming sext i1 instructions that codegen to terrible code. e.g.
int blah(_Bool x, _Bool y) {
  return (x - y) + 1;
}
=>
        movzbl  %dil, %eax
        movzbl  %sil, %ecx
        shll    $31, %ecx
        sarl    $31, %ecx
        leal    1(%rax,%rcx), %eax
        ret


Without the rule, llvm now generates:
        movzbl  %sil, %ecx
        movzbl  %dil, %eax
        incl    %eax
        subl    %ecx, %eax
        ret

It also helps with ARM (and pretty much any target that doesn't have a sext i1 :-).

The transformation was done as part of Eli's r75531. He has given the ok to
remove it.

rdar://11748024


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159230 91177308-0d34-0410-b5e6-96231b3b80d8

2012-06-26 22:03:13 +00:00

CMakeLists.txt

llvm/lib: [CMake] Add explicit dependency to intrinsics_gen.

2012-06-24 13:32:01 +00:00

InstCombine.h

add a new pass to instrument loads and stores for run-time bounds checking

2012-05-22 17:19:09 +00:00

InstCombineAddSub.cpp

Remove a instcombine transform that (no longer?) makes sense:

2012-06-26 22:03:13 +00:00

InstCombineAndOrXor.cpp

InstCombine: fix a bug when combining (fcmp cc0 x, y) && (fcmp cc1 x, y).