llvm/test/Transforms/InstCombine
David Majnemer 5624046453 InstCombine: Simplify (A ^ B) or/and (A ^ B ^ C)
While we can already transform A | (A ^ B) into A | B, things get bad
once we have (A ^ B) | (A ^ B ^ Cst) because reassociation will morph
this into (A ^ B) | ((A ^ Cst) ^ B).  Our existing patterns fail once
this happens.

To fix this, we add a new pattern which looks through the tree of xor
binary operators to see that, in fact, there exists a redundant xor
operation.

What follows bellow is a correctness proof of the transform using CVC3.

$ cat t.cvc
A, B, C : BITVECTOR(64);

QUERY BVXOR(A, B) | BVXOR(BVXOR(B, C), A) = BVXOR(A, B) | C;
QUERY BVXOR(BVXOR(A, C), B) | BVXOR(A, B) = BVXOR(A, B) | C;

QUERY BVXOR(A, B) & BVXOR(BVXOR(B, C), A) = BVXOR(A, B) & ~C;
QUERY BVXOR(BVXOR(A, C), B) & BVXOR(A, B) = BVXOR(A, B) & ~C;

$ cvc3 < t.cvc
Valid.
Valid.
Valid.
Valid.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214342 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-30 21:26:37 +00:00
..
2002-03-11-InstCombineHang.ll
2002-05-14-SubFailure.ll
2002-08-02-CastTest.ll
2002-12-05-MissedConstProp.ll
2003-05-26-CastMiscompile.ll
2003-05-27-ConstExprCrash.ll
2003-06-05-BranchInvertInfLoop.ll
2003-07-21-ExternalConstant.ll
2003-08-12-AllocaNonNull.ll
2003-09-09-VolatileLoadElim.ll
2003-10-29-CallSiteResolve.ll
2003-11-03-VarargsCallBug.ll
2004-01-13-InstCombineInvokePHI.ll
2004-02-23-ShiftShiftOverflow.ll
2004-03-13-InstCombineInfLoop.ll
2004-04-04-InstCombineReplaceAllUsesWith.ll
2004-05-07-UnsizedCastLoad.ll
2004-07-27-ConstantExprMul.ll
2004-08-09-RemInfLoop.ll
2004-08-10-BoolSetCC.ll
2004-09-20-BadLoadCombine2.ll
2004-09-20-BadLoadCombine.ll
2004-09-28-BadShiftAndSetCC.ll
2004-11-22-Missed-and-fold.ll
2004-11-27-SetCCForCastLargerAndConstant.ll
2004-12-08-RemInfiniteLoop.ll
2005-03-04-ShiftOverflow.ll
2005-04-07-UDivSelectCrash.ll
2005-06-15-DivSelectCrash.ll
2005-06-15-ShiftSetCCCrash.ll
2005-06-16-RangeCrash.ll
2005-06-16-SetCCOrSetCCMiscompile.ll
2005-07-07-DeadPHILoop.ll
2006-02-13-DemandedMiscompile.ll
2006-02-28-Crash.ll
2006-03-30-ExtractElement.ll
2006-04-28-ShiftShiftLongLong.ll
2006-05-04-DemandedBitCrash.ll
2006-09-15-CastToBool.ll
2006-10-19-SignedToUnsignedCastAndConst-2.ll
2006-10-20-mask.ll
2006-10-26-VectorReassoc.ll
2006-11-10-ashr-miscompile.ll
2006-12-01-BadFPVectorXform.ll
2006-12-05-fp-to-int-ext.ll
2006-12-08-Phi-ICmp-Op-Fold.ll
2006-12-08-Select-ICmp.ll
2006-12-15-Range-Test.ll
2006-12-23-Select-Cmp-Cmp.ll
2007-01-13-ExtCompareMiscompile.ll
2007-01-14-FcmpSelf.ll
2007-01-18-VectorInfLoop.ll
2007-01-27-AndICmp.ll
2007-02-01-LoadSinkAlloca.ll
2007-02-07-PointerCast.ll
2007-02-23-PhiFoldInfLoop.ll
2007-03-13-CompareMerge.ll
2007-03-19-BadTruncChangePR1261.ll
2007-03-21-SignedRangeTest.ll
2007-03-25-BadShiftMask.ll
2007-03-25-DoubleShift.ll
2007-03-26-BadShiftMask.ll
2007-04-08-SingleEltVectorCrash.ll
2007-05-10-icmp-or.ll
2007-05-14-Crash.ll
2007-05-18-CastFoldBug.ll
2007-06-06-AshrSignBit.ll
2007-06-21-DivCompareMiscomp.ll
2007-08-02-InfiniteLoop.ll
2007-09-10-AliasConstFold.ll
2007-09-17-AliasConstFold2.ll
2007-10-10-EliminateMemCpy.ll
2007-10-12-Crash.ll
2007-10-28-stacksave.ll
2007-10-31-RangeCrash.ll
2007-10-31-StringCrash.ll
2007-11-07-OpaqueAlignCrash.ll
2007-11-15-CompareMiscomp.ll
2007-11-22-IcmpCrash.ll
2007-11-25-CompatibleAttributes.ll
2007-12-10-ConstFoldCompare.ll
2007-12-12-GEPScale.ll
2007-12-16-AsmNoUnwind.ll
2007-12-18-AddSelCmpSub.ll
2007-12-28-IcmpSub2.ll
2008-01-06-BitCastAttributes.ll
2008-01-06-CastCrash.ll
2008-01-06-VoidCast.ll
2008-01-13-AndCmpCmp.ll
2008-01-13-NoBitCastAttributes.ll
2008-01-14-VarArgTrampoline.ll
2008-01-21-MismatchedCastAndCompare.ll
2008-01-21-MulTrunc.ll
2008-01-27-FloatSelect.ll
2008-01-29-AddICmp.ll
2008-02-13-MulURem.ll
2008-02-16-SDivOverflow2.ll
2008-02-16-SDivOverflow.ll
2008-02-23-MulSub.ll
2008-02-28-OrFCmpCrash.ll
2008-03-13-IntToPtr.ll
2008-04-22-ByValBitcast.ll
2008-04-28-VolatileStore.ll
2008-04-29-VolatileLoadDontMerge.ll
2008-04-29-VolatileLoadMerge.ll
2008-05-08-LiveStoreDelete.ll
2008-05-08-StrLenSink.ll
2008-05-09-SinkOfInvoke.ll
2008-05-17-InfLoop.ll
2008-05-18-FoldIntToPtr.ll
2008-05-22-IDivVector.ll
2008-05-22-NegValVector.ll
2008-05-23-CompareFold.ll
2008-05-31-AddBool.ll
2008-05-31-Bools.ll
2008-06-05-ashr-crash.ll
2008-06-08-ICmpPHI.ll
2008-06-13-InfiniteLoopStore.ll
2008-06-13-ReadOnlyCallStore.ll
2008-06-19-UncondLoad.ll
2008-06-21-CompareMiscomp.ll
2008-06-24-StackRestore.ll
2008-07-08-AndICmp.ll
2008-07-08-ShiftOneAndOne.ll
2008-07-08-SubAnd.ll
2008-07-08-VolatileLoadMerge.ll
2008-07-09-SubAndError.ll
2008-07-10-CastSextBool.ll
2008-07-10-ICmpBinOp.ll
2008-07-11-RemAnd.ll
2008-07-13-DivZero.ll
2008-07-16-fsub.ll
2008-07-16-sse2_storel_dq.ll
2008-08-05-And.ll
2008-08-17-ICmpXorSignbit.ll
2008-09-02-VectorCrash.ll
2008-09-29-FoldingOr.ll
2008-10-11-DivCompareFold.ll
2008-10-23-ConstFoldWithoutMask.ll
2008-11-01-SRemDemandedBits.ll
2008-11-08-FCmp.ll
2008-11-20-DivMulRem.ll
2008-11-27-IDivVector.ll
2008-11-27-MultiplyIntVec.ll
2008-11-27-UDivNegative.ll
2008-12-17-SRemNegConstVec.ll
2009-01-05-i128-crash.ll
2009-01-08-AlignAlloca.ll
2009-01-16-PointerAddrSpace.ll
2009-01-19-fmod-constant-float-specials.ll
2009-01-19-fmod-constant-float.ll
2009-01-24-EmptyStruct.ll
2009-01-31-InfIterate.ll
2009-01-31-Pressure.ll
2009-02-04-FPBitcast.ll
2009-02-11-NotInitialized.ll
2009-02-20-InstCombine-SROA.ll
2009-02-21-LoadCST.ll
2009-02-25-CrashZeroSizeArray.ll
2009-03-18-vector-ashr-crash.ll
2009-03-20-AShrOverShift.ll
2009-03-24-InfLoop.ll
2009-04-07-MulPromoteToI96.ll
2009-05-23-FCmpToICmp.ll
2009-06-11-StoreAddrSpace.ll
2009-06-16-SRemDemandedBits.ll
2009-07-02-MaskedIntVector.ll
2009-12-17-CmpSelectNull.ll
2010-01-28-NegativeSRem.ll
2010-03-03-ExtElim.ll IR: Fold away compares between GV GEPs and GVs 2014-07-04 22:05:26 +00:00
2010-05-30-memcpy-Struct.ll
2010-11-01-lshr-mask.ll
2010-11-21-SizeZeroTypeGEP.ll
2010-11-23-Distributed.ll
2011-02-14-InfLoop.ll
2011-03-08-SRemMinusOneBadOpt.ll
2011-05-02-VectorBoolean.ll
2011-05-13-InBoundsGEP.ll
2011-05-28-swapmulsub.ll
2011-06-13-nsw-alloca.ll
2011-09-03-Trampoline.ll
2011-10-07-AlignPromotion.ll
2012-3-15-or-xor-constant.ll
2012-6-7-vselect-bitcast.ll
2012-01-11-OpaqueBitcastCrash.ll
2012-02-13-FCmp.ll
2012-02-28-ICmp.ll
2012-03-10-InstCombine.ll
2012-04-23-Neon-Intrinsics.ll AArch64/ARM64: move ARM64 into AArch64's place 2014-05-24 12:50:23 +00:00
2012-04-24-vselect.ll
2012-04-30-SRem.ll
2012-05-27-Negative-Shift-Crash.ll
2012-05-28-select-hang.ll
2012-06-06-LoadOfPHIs.ll
2012-07-25-LoadPart.ll
2012-07-30-addrsp-bitcast.ll Allow aliases to be unnamed_addr. 2014-06-06 01:20:28 +00:00
2012-08-28-udiv_ashl.ll
2012-09-17-ZeroSizedAlloca.ll
2012-09-24-MemcpyFromGlobalCrash.ll
2012-10-25-vector-of-pointers.ll
2012-12-14-simp-vgep.ll
2013-03-05-Combine-BitcastTy-Into-Alloca.ll
abs_abs.ll This removes TODO added in http://reviews.llvm.org/D3658 2014-06-12 14:06:00 +00:00
abs-1.ll
add2.ll Added instruction combine to transform few more negative values addition to subtraction (Part 3) 2014-06-27 07:47:35 +00:00
add3.ll
add4.ll
add-shrink.ll Convert test to FileCheck. 2014-06-02 21:23:54 +00:00
add-sitofp.ll [InstCombine] mark ADD with nuw if no unsigned overflow 2014-06-17 00:42:07 +00:00
add.ll
addnegneg.ll
AddOverFlow.ll [ValueTracking] Extend range metadata to call/invoke 2014-06-19 16:50:16 +00:00
addrspacecast.ll InstCombine: Canonicalize addrspacecast between different element types 2014-06-06 21:52:55 +00:00
adjust-for-sminmax.ll
align-2d-gep.ll Make instsimplify's analysis of icmp eq/ne use computeKnownBits to determine whether the icmp is always true or false. Patch by Suyog Sarda! 2014-06-19 03:35:49 +00:00
align-addr.ll
align-attr.ll Make use of the align parameter attribute for all pointer arguments 2014-07-22 16:58:55 +00:00
align-external.ll
alloca.ll InstCombine: don't drop 'inalloca' in PromoteCastOfAllocation (PR19569) 2014-04-28 17:40:03 +00:00
and2.ll
and-compare.ll
and-fcmp.ll
and-not-or.ll
and-or-and.ll
and-or-not.ll
and-or.ll
and-xor-merge.ll
and-xor-or.ll
and.ll
apint-add1.ll
apint-add2.ll
apint-and1.ll
apint-and2.ll
apint-and-compare.ll
apint-and-or-and.ll
apint-and-xor-merge.ll
apint-call-cast-target.ll
apint-cast-and-cast.ll
apint-cast-cast-to-and.ll
apint-cast.ll
apint-div1.ll
apint-div2.ll
apint-mul1.ll
apint-mul2.ll
apint-not.ll
apint-or1.ll
apint-or2.ll
apint-rem1.ll
apint-rem2.ll
apint-select.ll
apint-shift-simplify.ll
apint-shift.ll
apint-shl-trunc.ll
apint-sub.ll
apint-xor1.ll
apint-xor2.ll
apint-zext1.ll
apint-zext2.ll
assume.ll Canonicalization for @llvm.assume 2014-07-25 21:45:17 +00:00
atomic.ll
badmalloc.ll
binop-cast.ll
bit-checks.ll
bit-tracking.ll
bitcast-alias-function.ll Allow alias to point to an arbitrary ConstantExpr. 2014-06-03 02:41:57 +00:00
bitcast-bigendian.ll
bitcast-sext-vector.ll
bitcast-store.ll
bitcast-vec-canon.ll
bitcast-vec-uniform.ll
bitcast-vector-fold.ll
bitcast.ll
bitcount.ll
bittest.ll
blend_x86.ll Post-commit fixes for r209643 2014-05-27 16:54:33 +00:00
bswap-fold.ll
bswap.ll
call2.ll
call-cast-target-inalloca.ll IR: Conservatively verify inalloca arguments 2014-04-30 17:22:00 +00:00
call-cast-target.ll
call-intrinsics.ll
call.ll
canonicalize_branch.ll
cast_ptr.ll
cast-call-combine.ll
cast-mul-select.ll
cast-set.ll
cast.ll Add back commit r210029. 2014-06-02 22:01:04 +00:00
ceil.ll
compare-signs.ll
constant-expr-datalayout.ll
constant-fold-address-space-pointer.ll Canonicalize addrspacecast ConstExpr between different pointer types 2014-06-15 21:40:57 +00:00
constant-fold-compare.ll
constant-fold-gep.ll
constant-fold-math.ll
copysign.ll
cos-1.ll
cos-2.ll
CPP_min_max.ll
crash.ll
dce-iterate.ll
deadcode.ll
debug-line.ll
debuginfo.ll
descale-zero.ll InstCombine: Fix a crash in Descale for multiply-by-zero 2014-07-10 17:13:27 +00:00
devirt.ll
disable-simplify-libcalls.ll
distribute.ll This patch removed duplicate code for matching patterns 2014-06-26 08:57:33 +00:00
div-shift-crash.ll
div-shift.ll
div.ll Optimize integral reciprocal (udiv 1, x and sdiv 1, x) to not use division. This fires exactly once in a clang bootstrap, but covers a few different results from http://www.cs.utah.edu/~regehr/souper/ 2014-05-14 03:03:05 +00:00
double-float-shrink-1.ll
double-float-shrink-2.ll
enforce-known-alignment.ll
err-rep-cold.ll
exact.ll
exp2-1.ll
exp2-2.ll
ExtractCast.ll
extractvalue.ll
fast-math.ll
fcmp-select.ll
fcmp-special.ll
fcmp.ll
fdiv.ll
ffs-1.ll [InstCombine] mark ADD with nuw if no unsigned overflow 2014-06-17 00:42:07 +00:00
float-shrink-compare.ll
fmul.ll
fneg-ext.ll
fold-bin-operand.ll
fold-calls.ll
fold-fops-into-selects.ll
fold-phi.ll
fold-sqrt-sqrtf.ll
fold-vector-select.ll
fold-vector-zero.ll
fp-ret-bitcast.ll
fpcast.ll
fpextend_x86.ll
fpextend.ll
fprintf-1.ll
fputs-1.ll
fsub.ll
fwrite-1.ll
gep-addrspace.ll
gepgep.ll
gepphigep.ll Add support for combining GEPs across PHI nodes 2014-05-29 20:29:47 +00:00
getelementptr.ll InstCombine: Canonicalize addrspacecast between different element types 2014-06-06 21:52:55 +00:00
hoist_instr.ll
icmp-logical.ll
icmp-shr.ll This patch implements optimization as mentioned in PR19753: Optimize comparisons with "ashr/lshr exact" of a constanst. 2014-07-22 19:19:36 +00:00
icmp.ll Look through addrspacecasts when turning ptr comparisons into 2014-06-09 19:20:29 +00:00
idioms.ll
insert-extract-shuffle.ll
IntPtrCast.ll
intrinsics.ll InstCombine: Strength reduce sadd.with.overflow into a regular nsw add if we can prove that it cannot overflow. 2014-07-04 10:22:21 +00:00
invariant.ll
invoke.ll
isascii-1.ll
isdigit-1.ll
JavaCompare.ll
known_align.ll
LandingPadClauses.ll
load3.ll
load-addrspace-cast.ll
load-cmp.ll
load-select.ll
load.ll Convert test to FileCheck. 2014-07-15 00:07:27 +00:00
loadstore-alignment.ll Teach computeKnownBits to look through addrspacecast. 2014-07-15 01:55:03 +00:00
logical-select.ll
lshr-phi.ll
malloc-free-delete.ll
memcmp-1.ll
memcmp-2.ll
memcpy_chk-1.ll
memcpy_chk-2.ll
memcpy-1.ll
memcpy-2.ll
memcpy-from-global.ll InstCombine: Canonicalize addrspacecast between different element types 2014-06-06 21:52:55 +00:00
memcpy-to-load.ll
memcpy.ll
memmove_chk-1.ll
memmove_chk-2.ll
memmove-1.ll
memmove-2.ll
memmove.ll
memset2.ll
memset_chk-1.ll
memset_chk-2.ll
memset-1.ll
memset-2.ll
memset.ll
merge-icmp.ll
mul-masked-bits.ll
mul.ll
multi-size-address-space-pointer.ll
multi-use-or.ll
narrow.ll
neon-intrinsics.ll
no-negzero.ll
not-fcmp.ll
not.ll
nothrow.ll
nsw.ll
obfuscated_splat.ll
objsize-64.ll
objsize-address-space.ll
objsize.ll
odr-linkage.ll
onehot_merge.ll
or-fcmp.ll
or-to-xor.ll
or-xor.ll InstCombine: Simplify (A ^ B) or/and (A ^ B ^ C) 2014-07-30 21:26:37 +00:00
or.ll Added InstCombine Transform for patterns: 2014-07-22 18:09:41 +00:00
osx-names.ll
overflow-mul.ll InstCombine: Disable umul.with.overflow recognition for vectors. 2014-06-24 10:47:52 +00:00
overflow.ll
OverlappingInsertvalues.ll [InstCombine] Some cleanup in optimization of redundant insertvalue instructions. 2014-05-08 19:50:24 +00:00
phi-merge-gep.ll
phi-select-constexpr.ll
phi.ll
pow-1.ll
pow-2.ll
pow-3.ll
pr2645-0.ll
pr2645-1.ll
pr2996.ll
pr8547.ll
pr12251.ll
pr12338.ll
pr17827.ll
pr19420.ll Revert "Revert r206045, "Fix shift by constants for vector."" 2014-04-14 21:50:37 +00:00
pr20059.ll removed duplicate testcase 2014-07-09 17:49:58 +00:00
pr20079.ll IR: Fold away compares between GV GEPs and GVs 2014-07-04 22:05:26 +00:00
PR7357.ll
preserve-sminmax.ll
printf-1.ll
printf-2.ll
ptr-int-cast.ll
puts-1.ll
r600-intrinsics.ll R600/SI: Add intrinsics for various math instructions. 2014-06-19 01:19:19 +00:00
README.txt
rem.ll Add back commit r210029. 2014-06-02 22:01:04 +00:00
round.ll
sdiv-1.ll
sdiv-2.ll
select-2.ll
select-crash.ll
select-extractelement.ll
select-load-call.ll
select-select.ll
select.ll [InstCombine] mark ADD with nuw if no unsigned overflow 2014-06-17 00:42:07 +00:00
set.ll
setcc-strength-reduce.ll
sext.ll Add back commit r210029. 2014-06-02 22:01:04 +00:00
shift-sra.ll
shift.ll Revert "Revert r206045, "Fix shift by constants for vector."" 2014-04-14 21:50:37 +00:00
shufflemask-undef.ll
shufflevec-constant.ll
sign-test-and-or.ll
signed-comparison.ll
signext.ll
simplify-demanded-bits-pointer.ll
simplify-libcalls.ll
sincospi.ll
sink_instruction.ll
sitofp.ll
sprintf-1.ll
sqrt.ll
srem1.ll
srem-simplify-bug.ll
srem.ll
stack-overalign.ll
stacksaverestore.ll
store.ll
stpcpy_chk-1.ll
stpcpy_chk-2.ll
stpcpy-1.ll
stpcpy-2.ll
strcat-1.ll
strcat-2.ll
strcat-3.ll
strchr-1.ll
strchr-2.ll
strcmp-1.ll
strcmp-2.ll
strcpy_chk-1.ll
strcpy_chk-2.ll
strcpy_chk-64.ll
strcpy-1.ll
strcpy-2.ll
strcspn-1.ll
strcspn-2.ll
strlen-1.ll Fold strlen(expr ? "str1" : "str2") to x ? len1 : len2. This fires about 330 times in a bootstrap of clang. 2014-05-02 04:11:45 +00:00
strlen-2.ll
strncat-1.ll
strncat-2.ll
strncat-3.ll
strncmp-1.ll
strncmp-2.ll
strncpy_chk-1.ll
strncpy_chk-2.ll
strncpy-1.ll
strncpy-2.ll
strpbrk-1.ll
strpbrk-2.ll
strrchr-1.ll
strrchr-2.ll
strspn-1.ll
strstr-1.ll
strstr-2.ll
strto-1.ll
struct-assign-tbaa.ll
sub-xor.ll
sub.ll InstCombine: Optimize x/INT_MIN to x==INT_MIN 2014-07-02 06:42:13 +00:00
toascii-1.ll
trunc.ll
udiv_select_to_select_shift.ll
udiv-simplify-bug-0.ll
udiv-simplify-bug-1.ll
udivrem-change-width.ll
urem-simplify-bug.ll
urem.ll
vec_demanded_elts.ll Also handle ConstantAggregateZero when optimizing vpermilvar*. 2014-04-29 22:20:40 +00:00
vec_extract_2elts.ll
vec_extract_elt.ll
vec_extract_var_elt.ll
vec_insertelt.ll
vec_narrow.ll
vec_phi_extract.ll
vec_sext.ll
vec_shuffle.ll InstCombine: Don't try to reorder shuffles where the mask is a ConstantExpr. 2014-06-24 10:38:10 +00:00
vector_gep1.ll
vector_gep2.ll
vector-casts.ll
vector-mul.ll
vector-srem.ll
vector-type.ll
volatile_store.ll
weak-symbols.ll
win-math.ll
x86-crc32-demanded.ll
xor2.ll InstCombine: Simplify (A ^ B) or/and (A ^ B ^ C) 2014-07-30 21:26:37 +00:00
xor-undef.ll
xor.ll
zero-point-zero-add.ll
zeroext-and-reduce.ll
zext-bool-add-sub.ll Add back commit r210029. 2014-06-02 22:01:04 +00:00
zext-fold.ll
zext-or-icmp.ll
zext.ll

This directory contains test cases for the instcombine transformation.  The
dated tests are actual bug tests, whereas the named tests are used to test
for features that the this pass should be capable of performing.