[msan] Fix handling of select with struct arguments.

llvm-svn: 189796
This commit is contained in:
Evgeniy Stepanov 2013-09-03 13:05:29 +00:00
parent d4183dabd7
commit e95d37c81d
2 changed files with 27 additions and 3 deletions

View File

@ -1744,11 +1744,22 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
void visitSelectInst(SelectInst& I) {
IRBuilder<> IRB(&I);
// a = select b, c, d
// Sa = (sext Sb) | (select b, Sc, Sd)
Value *S = IRB.CreateSelect(I.getCondition(), getShadow(I.getTrueValue()),
getShadow(I.getFalseValue()));
Value *S2 = IRB.CreateSExt(getShadow(I.getCondition()), S->getType());
setShadow(&I, IRB.CreateOr(S, S2, "_msprop"));
if (I.getType()->isAggregateType()) {
// To avoid "sign extending" i1 to an arbitrary aggregate type, we just do
// an extra "select". This results in much more compact IR.
// Sa = select Sb, poisoned, (select b, Sc, Sd)
S = IRB.CreateSelect(getShadow(I.getCondition()),
getPoisonedShadow(getShadowTy(I.getType())), S,
"_msprop_select_agg");
} else {
// Sa = (sext Sb) | (select b, Sc, Sd)
S = IRB.CreateOr(
S, IRB.CreateSExt(getShadow(I.getCondition()), S->getType()),
"_msprop_select");
}
setShadow(&I, S);
if (MS.TrackOrigins) {
// Origins are always i32, so any vector conditions must be flattened.
// FIXME: consider tracking vector origins for app vectors?

View File

@ -290,6 +290,19 @@ entry:
; CHECK-ORIGINS: ret <8 x i16>
define { i64, i64 } @SelectStruct(i1 zeroext %x, { i64, i64 } %a, { i64, i64 } %b) readnone sanitize_memory {
entry:
%c = select i1 %x, { i64, i64 } %a, { i64, i64 } %b
ret { i64, i64 } %c
}
; CHECK: @SelectStruct
; CHECK: select i1 {{.*}}, { i64, i64 }
; CHECK-NEXT: select i1 {{.*}}, { i64, i64 } { i64 -1, i64 -1 }, { i64, i64 }
; CHECK-NEXT: select i1 {{.*}}, { i64, i64 }
; CHECK: ret { i64, i64 }
define i8* @IntToPtr(i64 %x) nounwind uwtable readnone sanitize_memory {
entry:
%0 = inttoptr i64 %x to i8*