From 4798aaa1b25a0f1b7b4e354c3d254c34dadfa5c5 Mon Sep 17 00:00:00 2001 From: Craig Topper Date: Wed, 11 Apr 2018 01:09:10 +0000 Subject: [X86] In X86FlagsCopyLowering, when rewriting a memory setcc we need to emit an explicit MOV8mr instruction. Previously the code only knew how to handle setcc to a register. This should fix a crash in the chromium build. Change-Id: I4148fa048cd13db40bf45c18d4703492fde71b1f git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@329771 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/X86/X86FlagsCopyLowering.cpp | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) (limited to 'lib/Target/X86/X86FlagsCopyLowering.cpp') diff --git a/lib/Target/X86/X86FlagsCopyLowering.cpp b/lib/Target/X86/X86FlagsCopyLowering.cpp index 1f4bd7fd501..a101f6b7127 100644 --- a/lib/Target/X86/X86FlagsCopyLowering.cpp +++ b/lib/Target/X86/X86FlagsCopyLowering.cpp @@ -727,8 +727,27 @@ void X86FlagsCopyLoweringPass::rewriteSetCC(MachineBasicBlock &TestMBB, if (!CondReg) CondReg = promoteCondToReg(TestMBB, TestPos, TestLoc, Cond); - // Rewriting this is trivial: we just replace the register and remove the - // setcc. - MRI->replaceRegWith(SetCCI.getOperand(0).getReg(), CondReg); + // Rewriting a register def is trivial: we just replace the register and + // remove the setcc. + if (!SetCCI.mayStore()) { + assert(SetCCI.getOperand(0).isReg() && + "Cannot have a non-register defined operand to SETcc!"); + MRI->replaceRegWith(SetCCI.getOperand(0).getReg(), CondReg); + SetCCI.eraseFromParent(); + return; + } + + // Otherwise, we need to emit a store. + auto MIB = BuildMI(*SetCCI.getParent(), SetCCI.getIterator(), + SetCCI.getDebugLoc(), TII->get(X86::MOV8mr)); + // Copy the address operands. + for (int i = 0; i < X86::AddrNumOperands; ++i) + MIB.add(SetCCI.getOperand(i)); + + MIB.addReg(CondReg); + + MIB->setMemRefs(SetCCI.memoperands_begin(), SetCCI.memoperands_end()); + SetCCI.eraseFromParent(); + return; } -- cgit v1.2.3