Do not delete BBs if their addresses are taken. rdar://12396696

llvm-svn: 164866
This commit is contained in:
Evan Cheng 2012-09-28 23:58:57 +00:00
parent 6a8730f5dd
commit baf11248e4
2 changed files with 56 additions and 2 deletions

View File

@ -226,7 +226,8 @@ bool CodeGenPrepare::EliminateFallThrough(Function &F) {
// edge, just collapse it.
BasicBlock *SinglePred = BB->getSinglePredecessor();
if (!SinglePred || SinglePred == BB) continue;
// Don't merge if BB's address is taken.
if (!SinglePred || SinglePred == BB || BB->hasAddressTaken()) continue;
BranchInst *Term = dyn_cast<BranchInst>(SinglePred->getTerminator());
if (Term && !Term->isConditional()) {
@ -788,7 +789,7 @@ bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) {
}
// If we eliminated all predecessors of the block, delete the block now.
if (Changed && pred_begin(BB) == pred_end(BB))
if (Changed && !BB->hasAddressTaken() && pred_begin(BB) == pred_end(BB))
BB->eraseFromParent();
return Changed;

View File

@ -0,0 +1,53 @@
; RUN: llc -mtriple=i386-apple-macosx < %s | FileCheck %s
; rdar://12396696
@JT = global [4 x i32] [i32 sub (i32 ptrtoint (i8* blockaddress(@h, %18) to i32), i32 ptrtoint (i8* blockaddress(@h, %11) to i32)), i32 sub (i32 ptrtoint (i8* blockaddress(@h, %17) to i32), i32 ptrtoint (i8* blockaddress(@h, %11) to i32)), i32 sub (i32 ptrtoint (i8* blockaddress(@h, %22) to i32), i32 ptrtoint (i8* blockaddress(@h, %18) to i32)), i32 sub (i32 ptrtoint (i8* blockaddress(@h, %22) to i32), i32 ptrtoint (i8* blockaddress(@h, %17) to i32))]
@gGlobalLock = external global i8*
@.str40 = external global [35 x i8]
; CHECK: _JT:
; CHECK-NOT: .long Ltmp{{[0-9]+}}-1
; CHECK-NOT: .long 1-Ltmp{{[0-9]+}}
; CHECK: .long Ltmp{{[0-9]+}}-Ltmp{{[0-9]+}}
; CHECK: .long Ltmp{{[0-9]+}}-Ltmp{{[0-9]+}}
; CHECK: .long Ltmp{{[0-9]+}}-Ltmp{{[0-9]+}}
; CHECK: .long Ltmp{{[0-9]+}}-Ltmp{{[0-9]+}}
define void @h(i8*) nounwind ssp {
%2 = alloca i8*
store i8* %0, i8** %2
%3 = load i8** %2
%4 = bitcast i8* %3 to { i32, i32 }*
%5 = getelementptr { i32, i32 }* %4, i32 0, i32 0
%6 = load i32* %5
%7 = srem i32 %6, 2
%8 = icmp slt i32 %6, 2
%9 = select i1 %8, i32 %6, i32 %7
%10 = icmp eq i32 %9, 0
br label %11
; <label>:11 ; preds = %1
%12 = zext i1 %10 to i32
%13 = getelementptr [4 x i32]* @JT, i32 0, i32 %12
%14 = load i32* %13
%15 = add i32 %14, ptrtoint (i8* blockaddress(@h, %11) to i32)
%16 = inttoptr i32 %15 to i8*
indirectbr i8* %16, [label %17, label %18]
; <label>:17 ; preds = %11
tail call void (i8*, ...)* @g(i8* getelementptr inbounds ([35 x i8]* @.str40, i32 0, i32 0))
br label %22
; <label>:18 ; preds = %11
%19 = call i32 @f(i32 -1037694186) nounwind
%20 = inttoptr i32 %19 to i32 (i8**)*
%21 = tail call i32 %20(i8** @gGlobalLock)
br label %22
; <label>:22 ; preds = %18, %17
ret void
}
declare i32 @f(i32)
declare void @g(i8*, ...)