Bill Wendling e1b66f1145 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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151691 91177308-0d34-0410-b5e6-96231b3b80d8		2012-02-29 01:46:50 +00:00
..
CMakeLists.txt
InstCombine.h
InstCombineAddSub.cpp
InstCombineAndOrXor.cpp	Restrict this transformation to equality conditions.	2012-02-29 01:46:50 +00:00
InstCombineCalls.cpp
InstCombineCasts.cpp
InstCombineCompares.cpp	Fix unsigned off-by-one in comment.	2012-02-21 13:40:06 +00:00
InstCombineLoadStoreAlloca.cpp
InstCombineMulDivRem.cpp
InstCombinePHI.cpp
InstCombineSelect.cpp
InstCombineShifts.cpp
InstCombineSimplifyDemanded.cpp
InstCombineVectorOps.cpp
InstCombineWorklist.h
InstructionCombining.cpp
LLVMBuild.txt
Makefile