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

[GlobalOpt] Check stored once value's type before setting global initializer 

In the provided test case, we were trying to set the global's
initializer to `i32* null` when the global's value type was `@0`.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D108232
This commit is contained in:
Arthur Eubanks 2021-08-17 12:00:45 -07:00
parent af78180936
commit 16890e0040
2 changed files with 24 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
llvm/lib/Transforms/IPO/GlobalOpt.cpp
View File

@ -1610,7 +1610,8 @@ processInternalGlobal(GlobalVariable *GV, const GlobalStatus &GS,
// initializer to be the stored value, then delete all stores to the
// global. This allows us to mark it constant.
if (Constant *SOVConstant = dyn_cast<Constant>(GS.StoredOnceValue))
if (isa<UndefValue>(GV->getInitializer())) {
if (SOVConstant->getType() == GV->getValueType() &&
isa<UndefValue>(GV->getInitializer())) {
// Change the initial value here.
GV->setInitializer(SOVConstant);

22
llvm/test/Transforms/GlobalOpt/stored-once-value-type.ll Normal file
View File

@ -0,0 +1,22 @@
; RUN: opt -passes=globalopt < %s -S | FileCheck %s
; Check that we don't try to set a global initializer to a value of a different type.
; In this case, we were trying to set @0's initializer to be i32* null.
%0 = type { i32* }
@0 = internal global %0* null
; CHECK: global %0 undef
define void @a() {
%1 = tail call i8* @_Znwm(i64 8)
%2 = bitcast i8* %1 to %0*
%3 = getelementptr inbounds %0, %0* %2, i64 0, i32 0
store i32* null, i32** %3, align 8
store i8* %1, i8** bitcast (%0** @0 to i8**), align 8
%4 = load i64*, i64** bitcast (%0** @0 to i64**), align 8
%5 = load atomic i64, i64* %4 acquire, align 8
ret void
}
declare i8* @_Znwm(i64)