From 1655b73734cc8f19160eb6be863203c571468d18 Mon Sep 17 00:00:00 2001 From: "Duncan P. N. Exon Smith" Date: Tue, 17 Dec 2013 20:28:21 +0000 Subject: [PATCH] Assert that the last operand is actually EFLAGS This is another follow-up to r197503, after a post-commit review by Andy. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197520 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/X86/X86ISelLowering.cpp | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp index c780c14abbc..e3f9963a715 100644 --- a/lib/Target/X86/X86ISelLowering.cpp +++ b/lib/Target/X86/X86ISelLowering.cpp @@ -15338,6 +15338,12 @@ X86TargetLowering::EmitVAStartSaveXMMRegsWithCustomInserter( MBB->addSuccessor(EndMBB); } + // Make sure the last operand is EFLAGS, which gets clobbered by the branch + // that was just emitted, but clearly shouldn't be "saved". + assert((MI->getNumOperands() <= 3 || + !MI->getOperand(MI->getNumOperands() - 1).isReg() || + MI->getOperand(MI->getNumOperands() - 1).getReg() == X86::EFLAGS) + && "Expected last argument to be EFLAGS"); unsigned MOVOpc = Subtarget->hasFp256() ? X86::VMOVAPSmr : X86::MOVAPSmr; // In the XMM save block, save all the XMM argument registers. for (int i = 3, e = MI->getNumOperands() - 1; i != e; ++i) {