Bill Wendling f2c78f344e Restrict this transformation to equality conditions. ...

This transformation is not correct for not-equal conditions:

(trunc x) != C1 & (and x, CA) != C2 -> (and x, CA|CMAX) != C1|C2

Let
  C1 == 0
  C2 == 0
  CA == 0xFF0000
  CMAX == 0xFF
and truncating to i8.

The original truth table:

    x   | A: trunc x != 0 | B: x & 0xFF0000 != 0 | A & B != 0
--------------------------------------------------------------
0x00000 |        0        |          0           |     0
0x00001 |        1        |          0           |     0
0x10000 |        0        |          1           |     0
0x10001 |        1        |          1           |     1

The truth table of the replacement:

    x   | x & 0xFF00FF != 0
----------------------------
0x00000 |        0
0x00001 |        1
0x10000 |        1
0x10001 |        1

So they are different.

llvm-svn: 151691

2012-02-29 01:46:50 +00:00

..

CMakeLists.txt

build/CMake: Finish removal of add_llvm_library_dependencies.

2011-11-29 19:25:30 +00:00

InstCombine.h

Fix a few more places where TargetData/TargetLibraryInfo is not being passed.

2011-12-02 01:26:24 +00:00

InstCombineAddSub.cpp

InstCombine: Make OptimizePointerDifference more aggressive.

2012-02-20 14:34:57 +00:00

InstCombineAndOrXor.cpp

Restrict this transformation to equality conditions.

2012-02-29 01:46:50 +00:00

InstCombineCalls.cpp

[unwind removal] We no longer have 'unwind' instructions being generated, so

2012-02-06 21:16:41 +00:00

InstCombineCasts.cpp

Remove some dead code and tidy things up now that vectors use ConstantDataVector

2012-02-06 21:56:39 +00:00

InstCombineCompares.cpp

Fix unsigned off-by-one in comment.

2012-02-21 13:40:06 +00:00

InstCombineLoadStoreAlloca.cpp

Use the getFirstInsertionPt() method instead of getFirstNonPHI + an 'isa<>'

2011-08-16 20:45:24 +00:00

InstCombineMulDivRem.cpp

Remove some dead code and tidy things up now that vectors use ConstantDataVector

2012-02-06 21:56:39 +00:00

InstCombinePHI.cpp

Update instcombine for atomic load/store.

2011-08-15 22:09:40 +00:00

InstCombineSelect.cpp

More dead code removal (using -Wunreachable-code)

2012-01-20 21:51:11 +00:00

InstCombineShifts.cpp

Convert assert(0) to llvm_unreachable

2012-02-07 05:05:23 +00:00

InstCombineSimplifyDemanded.cpp

continue making the world safe for ConstantDataVector. At this point,

2012-01-27 03:08:05 +00:00

InstCombineVectorOps.cpp

continue making the world safe for ConstantDataVector. At this point,

2012-01-27 03:08:05 +00:00

InstCombineWorklist.h

InstCombine: We know the number of items initially added to the worklist map, reserve space early to avoid rehashing.

2011-03-05 16:43:46 +00:00

InstructionCombining.cpp

Remove some dead code and tidy things up now that vectors use ConstantDataVector

2012-02-06 21:56:39 +00:00

LLVMBuild.txt

LLVMBuild: Remove trailing newline, which irked me.

2011-12-12 19:48:00 +00:00

Makefile

make -fno-rtti the default unless a directory builds with REQUIRES_RTTI.

2010-01-24 20:43:08 +00:00