maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[CGP] Fix common type handling in optimizeMemoryInst 

If common type is different we should bail out due to we will not be
able to create a select or Phi of these values.

Basically it is done in ExtAddrMode::compare however it does not work
if we handle the null first and then two values of different types.
so add a check in initializeMap as well. The check in ExtAddrMode::compare
is used as earlier bail out.

Reviewers: reames, john.brawn
Reviewed By: john.brawn
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40479

llvm-svn: 319292
This commit is contained in:
Serguei Katkov 2017-11-29 05:51:26 +00:00
parent 0010707e1c
commit 5036459ae3
2 changed files with 43 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
llvm/lib/CodeGen/CodeGenPrepare.cpp
View File

@ -2909,8 +2909,10 @@ public:
// Build a map between <original value, basic block where we saw it> to
// value of base register.
// Bail out if there is no common type.
FoldAddrToValueMapping Map;
initializeMap(Map);
if (!initializeMap(Map))
return false;
Value *CommonValue = findCommon(Map);
if (CommonValue)
@ -2924,7 +2926,8 @@ private:
/// If address is not an instruction than basic block is set to null.
/// At the same time we find a common type for different field we will
/// use to create new Phi/Select nodes. Keep it in CommonType field.
void initializeMap(FoldAddrToValueMapping &Map) {
/// Return false if there is no common type found.
bool initializeMap(FoldAddrToValueMapping &Map) {
// Keep track of keys where the value is null. We will need to replace it
// with constant null when we know the common type.
SmallVector<ValueInBB, 2> NullValue;
@ -2936,10 +2939,10 @@ private:
Value *DV = AM.GetFieldAsValue(DifferentField, IntPtrTy);
if (DV) {
if (CommonType)
assert(CommonType == DV->getType() && "Different types detected!");
else
CommonType = DV->getType();
auto *Type = DV->getType();
if (CommonType && CommonType != Type)
return false;
CommonType = Type;
Map[{ AM.OriginalValue, BB }] = DV;
} else {
NullValue.push_back({ AM.OriginalValue, BB });
@ -2948,6 +2951,7 @@ private:
assert(CommonType && "At least one non-null value must be!");
for (auto VIBB : NullValue)
Map[VIBB] = Constant::getNullValue(CommonType);
return true;
}
/// \brief We have mapping between value A and basic block where value A

33
llvm/test/Transforms/CodeGenPrepare/X86/sink-addrmode-base.ll
View File

@ -508,3 +508,36 @@ fallthrough:
%v = add i32 %v1, %v2
ret i32 %v
}
; Different types but null is the first?
define i32 @test19(i1 %cond1, i1 %cond2, i64* %b2, i8* %b1) {
; CHECK-LABEL: @test19
entry:
%g1 = getelementptr inbounds i64, i64* %b2, i64 5
%bc1 = bitcast i64* %g1 to i32*
br i1 %cond1, label %if.then1, label %if.then2
if.then1:
%g2 = getelementptr inbounds i8, i8* %b1, i64 40
%bc2 = bitcast i8* %g2 to i32*
br label %fallthrough
if.then2:
%bc1_1 = bitcast i64* %g1 to i32*
br i1 %cond2, label %fallthrough, label %if.then3
if.then3:
%g3 = getelementptr inbounds i64, i64* null, i64 5
%bc1_2 = bitcast i64* %g3 to i32*
br label %fallthrough
fallthrough:
; CHECK-NOT: sunk_phi
%c = phi i32* [%bc2, %if.then1], [%bc1_1, %if.then2], [%bc1_2, %if.then3]
%v1 = load i32, i32* %c, align 4
%g1_1 = getelementptr inbounds i64, i64* %b2, i64 5
%bc1_1_1 = bitcast i64* %g1_1 to i32*
%v2 = load i32, i32* %bc1_1_1, align 4
%v = add i32 %v1, %v2
ret i32 %v
}