Fix crash in PRE.

After r203553 overflow intrinsics and their non-intrinsic (normal)
instruction get hashed to the same value. This patch prevents PRE from
moving an instruction into a predecessor block, and trying to add a phi
node that gets two different types (the intrinsic result and the
non-intrinsic result), resulting in a failing assert.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203574 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Erik Verbruggen 2014-03-11 15:07:32 +00:00
parent d111694af2
commit 0638609d66
2 changed files with 26 additions and 0 deletions

View File

@ -2550,6 +2550,8 @@ bool GVN::performPRE(Function &F) {
predMap.push_back(std::make_pair(static_cast<Value *>(0), P)); predMap.push_back(std::make_pair(static_cast<Value *>(0), P));
PREPred = P; PREPred = P;
++NumWithout; ++NumWithout;
} else if (predV->getType() != CurInst->getType()) {
continue;
} else if (predV == CurInst) { } else if (predV == CurInst) {
/* CurInst dominates this predecessor. */ /* CurInst dominates this predecessor. */
NumWithout = 2; NumWithout = 2;

View File

@ -39,5 +39,29 @@ if.end: ; preds = %entry
; CHECK: ret i32 %sadd3.repl ; CHECK: ret i32 %sadd3.repl
} }
; Check if PRE does not crash
define i32 @pre(i32 %a, i32 %b) nounwind ssp uwtable {
entry:
%cmp = icmp sgt i32 %a, 42
br i1 %cmp, label %if.then, label %if.end3
if.then: ; preds = %entry
%add = call {i32, i1} @llvm.sadd.with.overflow.i32(i32 %a, i32 %b)
%add1 = extractvalue {i32, i1} %add, 0
%o = extractvalue {i32, i1} %add, 1
%o32 = zext i1 %o to i32
%add32 = add i32 %add1, %o32
%cmp1 = icmp sgt i32 %add1, 42
br i1 %cmp1, label %if.then2, label %if.end3
if.then2: ; preds = %if.then
call void @abort() noreturn
unreachable
if.end3: ; preds = %if.end, %entry
%add4 = add i32 %a, %b
ret i32 %add4
}
declare void @abort() noreturn
declare { i32, i1 } @llvm.sadd.with.overflow.i32(i32, i32) nounwind readnone declare { i32, i1 } @llvm.sadd.with.overflow.i32(i32, i32) nounwind readnone