From 53c86db25b5b4e163c68dc91c8ce1bc8180e6ff3 Mon Sep 17 00:00:00 2001 From: Hal Finkel Date: Thu, 11 Jul 2013 16:31:51 +0000 Subject: [PATCH] PPCDAGToDAGISel::isRunOfOnes should return false on zero This fixes a bug (found by csmith) at -O0 where we attempt to create a RLWIMI with an out-of-range operand. Most uses of the isRunOfOnes function are guarded by a condition that the value is not zero. This was not true in two places, and in both places a zero input would result in an out-of-rage MB value (= 32). To fix this, isRunOfOnes returns false on a zero input (and I've remove one now-redundant guard). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186101 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/PowerPC/PPCISelDAGToDAG.cpp | 5 ++++- test/CodeGen/PowerPC/zero-not-run.ll | 27 ++++++++++++++++++++++++++ 2 files changed, 31 insertions(+), 1 deletion(-) create mode 100644 test/CodeGen/PowerPC/zero-not-run.ll diff --git a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp index 901d3690972..475bde18efb 100644 --- a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp +++ b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp @@ -330,6 +330,9 @@ static bool isOpcWithIntImmediate(SDNode *N, unsigned Opc, unsigned& Imm) { } bool PPCDAGToDAGISel::isRunOfOnes(unsigned Val, unsigned &MB, unsigned &ME) { + if (!Val) + return false; + if (isShiftedMask_32(Val)) { // look for the first non-zero bit MB = countLeadingZeros(Val); @@ -435,7 +438,7 @@ SDNode *PPCDAGToDAGISel::SelectBitfieldInsert(SDNode *N) { } unsigned MB, ME; - if (InsertMask && isRunOfOnes(InsertMask, MB, ME)) { + if (isRunOfOnes(InsertMask, MB, ME)) { SDValue Tmp1, Tmp2; if ((Op1Opc == ISD::SHL || Op1Opc == ISD::SRL) && diff --git a/test/CodeGen/PowerPC/zero-not-run.ll b/test/CodeGen/PowerPC/zero-not-run.ll new file mode 100644 index 00000000000..04c4277bb47 --- /dev/null +++ b/test/CodeGen/PowerPC/zero-not-run.ll @@ -0,0 +1,27 @@ +; RUN: llc -O0 -mtriple=powerpc64-unknown-linux-gnu -mcpu=pwr7 < %s +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-f128:128:128-v128:128:128-n32:64" +target triple = "powerpc64-unknown-linux-gnu" + +; Function Attrs: nounwind +define internal i32* @func_65(i32* %p_66) #0 { +entry: + br i1 undef, label %for.body, label %for.end731 + +for.body: ; preds = %entry + %0 = load i32* undef, align 4 + %or31 = or i32 %0, 319143828 + store i32 %or31, i32* undef, align 4 + %cmp32 = icmp eq i32 319143828, %or31 + %conv33 = zext i1 %cmp32 to i32 + %conv34 = sext i32 %conv33 to i64 + %call35 = call i64 @safe_mod_func_uint64_t_u_u(i64 %conv34, i64 -10) + unreachable + +for.end731: ; preds = %entry + ret i32* undef +} + +; Function Attrs: nounwind +declare i64 @safe_mod_func_uint64_t_u_u(i64, i64) #0 + +attributes #0 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf"="true" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "unsafe-fp-math"="false" "use-soft-float"="false" } -- 2.34.1