From c4a3f23b9251b07785cca646ad27b426dfa23230 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Sun, 14 Mar 2010 19:46:02 +0000 Subject: [PATCH] fix ShrinkDemandedOps to not leave dead nodes around, fixing PR6607 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98512 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp | 6 ++++++ test/CodeGen/X86/crash.ll | 19 +++++++++++++++++++ 2 files changed, 25 insertions(+) diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp index f6828ae4fb3..72e61d33257 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp @@ -509,6 +509,12 @@ void SelectionDAGISel::ShrinkDemandedOps() { InWorklist.erase(N); if (N->use_empty() && N != CurDAG->getRoot().getNode()) { + // Deleting this node may make its operands dead, add them to the worklist + // if they aren't already there. + for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) + if (InWorklist.insert(N->getOperand(i).getNode())) + Worklist.push_back(N->getOperand(i).getNode()); + CurDAG->DeleteNode(N); continue; } diff --git a/test/CodeGen/X86/crash.ll b/test/CodeGen/X86/crash.ll index b75d2651ecb..cfa12701653 100644 --- a/test/CodeGen/X86/crash.ll +++ b/test/CodeGen/X86/crash.ll @@ -71,3 +71,22 @@ return: ; preds = %if.else, %entry } declare i32 @safe(i32) + +; PR6607 +define fastcc void @test5(i32 %FUNC) nounwind { +foo: + %0 = load i8* undef, align 1 ; [#uses=3] + %1 = sext i8 %0 to i32 ; [#uses=2] + %2 = zext i8 %0 to i32 ; [#uses=1] + %tmp1.i5037 = urem i32 %2, 10 ; [#uses=1] + %tmp.i5038 = icmp ugt i32 %tmp1.i5037, 15 ; [#uses=1] + %3 = zext i1 %tmp.i5038 to i8 ; [#uses=1] + %4 = icmp slt i8 %0, %3 ; [#uses=1] + %5 = add nsw i32 %1, 256 ; [#uses=1] + %storemerge.i.i57 = select i1 %4, i32 %5, i32 %1 ; [#uses=1] + %6 = shl i32 %storemerge.i.i57, 16 ; [#uses=1] + %7 = sdiv i32 %6, -256 ; [#uses=1] + %8 = trunc i32 %7 to i8 ; [#uses=1] + store i8 %8, i8* undef, align 1 + ret void +}