Don't constant propagate byval pointers, since they are not really pointers, but

rather structs passed by value.
This fixes PR5038.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82689 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Torok Edwin 2009-09-24 09:47:18 +00:00
parent 48f7ce88a6
commit 30a94e3b42
3 changed files with 30 additions and 1 deletions

View File

@ -130,7 +130,8 @@ bool IPCP::PropagateConstantsIntoArguments(Function &F) {
Function::arg_iterator AI = F.arg_begin();
for (unsigned i = 0, e = ArgumentConstants.size(); i != e; ++i, ++AI) {
// Do we have a constant argument?
if (ArgumentConstants[i].second || AI->use_empty())
if (ArgumentConstants[i].second || AI->use_empty() ||
(AI->hasByValAttr() && isa<PointerType>(AI->getType())))
continue;
Value *V = ArgumentConstants[i].first;

View File

@ -1267,6 +1267,10 @@ CallOverdefined:
for (Function::arg_iterator AI = F->arg_begin(), E = F->arg_end();
AI != E; ++AI, ++CAI) {
LatticeVal &IV = ValueState[AI];
if (AI->hasByValAttr() && isa<PointerType>(AI->getType())) {
IV.markOverdefined();
continue;
}
if (!IV.isOverdefined())
mergeInValue(IV, AI, getValueState(*CAI));
}

View File

@ -0,0 +1,24 @@
; RUN: llvm-as <%s | opt -ipsccp | llvm-dis | FileCheck %s
; Don't constant-propagate byval pointers, since they are not pointers!
; PR5038
%struct.MYstr = type { i8, i32 }
@mystr = internal global %struct.MYstr zeroinitializer ; <%struct.MYstr*> [#uses=3]
define internal void @vfu1(%struct.MYstr* byval align 4 %u) nounwind {
entry:
%0 = getelementptr %struct.MYstr* %u, i32 0, i32 1 ; <i32*> [#uses=1]
store i32 99, i32* %0, align 4
; CHECK: %struct.MYstr* %u
%1 = getelementptr %struct.MYstr* %u, i32 0, i32 0 ; <i8*> [#uses=1]
store i8 97, i8* %1, align 4
; CHECK: %struct.MYstr* %u
br label %return
return: ; preds = %entry
ret void
}
define void @unions() nounwind {
entry:
call void @vfu1(%struct.MYstr* byval align 4 @mystr) nounwind
ret void
}