From cc7052343e5e955d4e2f48885c06360f9003390a Mon Sep 17 00:00:00 2001 From: Bob Wilson Date: Fri, 15 Nov 2013 19:09:27 +0000 Subject: Avoid illegal integer promotion in fastisel Stop folding constant adds into GEP when the type size doesn't match. Otherwise, the adds' operands are effectively being promoted, changing the conditions of an overflow. Results are different when: sext(a) + sext(b) != sext(a + b) Problem originally found on x86-64, but also fixed issues with ARM and PPC, which used similar code. Patch by Duncan Exon Smith! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194840 91177308-0d34-0410-b5e6-96231b3b80d8 --- test/CodeGen/PowerPC/fastisel-gep-promote-before-add.ll | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) create mode 100644 test/CodeGen/PowerPC/fastisel-gep-promote-before-add.ll (limited to 'test/CodeGen/PowerPC') diff --git a/test/CodeGen/PowerPC/fastisel-gep-promote-before-add.ll b/test/CodeGen/PowerPC/fastisel-gep-promote-before-add.ll new file mode 100644 index 0000000..4bcacf0 --- /dev/null +++ b/test/CodeGen/PowerPC/fastisel-gep-promote-before-add.ll @@ -0,0 +1,17 @@ +; fastisel should not fold add with non-pointer bitwidth +; sext(a) + sext(b) != sext(a + b) +; RUN: llc -mtriple=powerpc64-unknown-freebsd10.0 %s -O0 -o - | FileCheck %s + +define zeroext i8 @gep_promotion(i8* %ptr) nounwind uwtable ssp { +entry: + %ptr.addr = alloca i8*, align 8 + %add = add i8 64, 64 ; 0x40 + 0x40 + %0 = load i8** %ptr.addr, align 8 + + ; CHECK-LABEL: gep_promotion: + ; CHECK: lbz {{[0-9]+}}, 0({{.*}}) + %arrayidx = getelementptr inbounds i8* %0, i8 %add + + %1 = load i8* %arrayidx, align 1 + ret i8 %1 +} -- cgit v1.1