Treat a call of function pointer like a load of the pointer when considering

whether the pointer can be replaced with the global variable it is a copy of.
Fixes PR8680.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120126 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nick Lewycky 2010-11-24 22:04:20 +00:00
parent 25958730df
commit 081f80078d
2 changed files with 19 additions and 1 deletions

View File

@ -1783,7 +1783,7 @@ static bool PointsToConstantGlobal(Value *V) {
/// see any stores or other unknown uses. If we see pointer arithmetic, keep
/// track of whether it moves the pointer (with isOffset) but otherwise traverse
/// the uses. If we see a memcpy/memmove that targets an unoffseted pointer to
/// the alloca, and if the source pointer is a pointer to a constant global, we
/// the alloca, and if the source pointer is a pointer to a constant global, we
/// can optimize this.
static bool isOnlyCopiedFromConstantGlobal(Value *V, MemTransferInst *&TheCopy,
bool isOffset) {
@ -1816,6 +1816,11 @@ static bool isOnlyCopiedFromConstantGlobal(Value *V, MemTransferInst *&TheCopy,
// load and we can ignore it.
if (CS.onlyReadsMemory())
continue;
// If this is the function being called then we treat it like a load and
// ignore it.
if (CS.isCallee(UI))
continue;
// If this is being passed as a byval argument, the caller is making a
// copy, so it is only a read of the alloca.

View File

@ -0,0 +1,13 @@
; RUN: opt -scalarrepl -disable-output %s
; PR8680
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
define void @main() nounwind {
entry:
%memtmp = alloca i32, align 4
%0 = bitcast i32* %memtmp to void ()*
call void %0() nounwind
ret void
}