diff options
| -rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 14 | ||||
| -rw-r--r-- | test/CodeGen/X86/2010-09-17-SideEffectsInChain.ll | 26 |
2 files changed, 33 insertions, 7 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index ad06ebda5b..77c40afe69 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -5478,9 +5478,9 @@ bool SDNode::isOperandOf(SDNode *N) const { /// reachesChainWithoutSideEffects - Return true if this operand (which must /// be a chain) reaches the specified operand without crossing any -/// side-effecting instructions. In practice, this looks through token -/// factors and non-volatile loads. In order to remain efficient, this only -/// looks a couple of nodes in, it does not do an exhaustive search. +/// side-effecting instructions on any chain path. In practice, this looks +/// through token factors and non-volatile loads. In order to remain efficient, +/// this only looks a couple of nodes in, it does not do an exhaustive search. bool SDValue::reachesChainWithoutSideEffects(SDValue Dest, unsigned Depth) const { if (*this == Dest) return true; @@ -5490,12 +5490,12 @@ bool SDValue::reachesChainWithoutSideEffects(SDValue Dest, if (Depth == 0) return false; // If this is a token factor, all inputs to the TF happen in parallel. If any - // of the operands of the TF reach dest, then we can do the xform. + // of the operands of the TF does not reach dest, then we cannot do the xform. if (getOpcode() == ISD::TokenFactor) { for (unsigned i = 0, e = getNumOperands(); i != e; ++i) - if (getOperand(i).reachesChainWithoutSideEffects(Dest, Depth-1)) - return true; - return false; + if (!getOperand(i).reachesChainWithoutSideEffects(Dest, Depth-1)) + return false; + return true; } // Loads don't have side effects, look through them. diff --git a/test/CodeGen/X86/2010-09-17-SideEffectsInChain.ll b/test/CodeGen/X86/2010-09-17-SideEffectsInChain.ll new file mode 100644 index 0000000000..35434ffafa --- /dev/null +++ b/test/CodeGen/X86/2010-09-17-SideEffectsInChain.ll @@ -0,0 +1,26 @@ +; RUN: llc < %s -combiner-alias-analysis -march=x86-64 | FileCheck %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-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64" +target triple = "x86_64-apple-darwin10.4" +declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32, i1) nounwind + +define fastcc i32 @cli_magic_scandesc(i8* %in) nounwind ssp { +entry: + %a = alloca [64 x i8] + %b = getelementptr inbounds [64 x i8]* %a, i64 0, i32 0 + %c = getelementptr inbounds [64 x i8]* %a, i64 0, i32 30 + %d = load i8* %b, align 8 + %e = load i8* %c, align 8 + %f = bitcast [64 x i8]* %a to i8* + call void @llvm.memcpy.p0i8.p0i8.i64(i8* %f, i8* %in, i64 64, i32 8, i1 false) nounwind + store i8 %d, i8* %b, align 8 + store i8 %e, i8* %c, align 8 + ret i32 0 +} + +; CHECK: movq ___stack_chk_guard@GOTPCREL(%rip), %rax +; CHECK: movb (%rsp), %dl +; CHECK-NEXT: movb 30(%rsp), %sil +; CHECK: movb %dl, (%rsp) +; CHECK-NEXT: movb %sil, 30(%rsp) +; CHECK: callq ___stack_chk_fail |