From 51dee24ca6ba63cf021d56ca9cbae62c739d5041 Mon Sep 17 00:00:00 2001 From: Andrew Trick Date: Tue, 15 Oct 2013 03:39:43 +0000 Subject: Improve on r192635, ExeDepsFix for avx, and add a test case. rdar:15221834 False AVX register dependencies cause 5x slowdown on flops-5/6 and significant slowdown on several others. This was blocking the switch to MI-Sched. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192669 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/ExecutionDepsFix.cpp | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/CodeGen/ExecutionDepsFix.cpp b/lib/CodeGen/ExecutionDepsFix.cpp index 0d26f9d..031f19c 100644 --- a/lib/CodeGen/ExecutionDepsFix.cpp +++ b/lib/CodeGen/ExecutionDepsFix.cpp @@ -557,6 +557,9 @@ void ExeDepsFix::processUndefReads(MachineBasicBlock *MBB) { for (MachineBasicBlock::reverse_iterator I = MBB->rbegin(), E = MBB->rend(); I != E; ++I) { + // Update liveness, including the current instrucion's defs. + LiveUnits.stepBackward(*I, *TRI); + if (UndefMI == &*I) { if (!LiveUnits.contains(UndefMI->getOperand(OpIdx).getReg(), *TRI)) TII->breakPartialRegDependency(UndefMI, OpIdx, TRI); @@ -568,7 +571,6 @@ void ExeDepsFix::processUndefReads(MachineBasicBlock *MBB) { UndefMI = UndefReads.back().first; OpIdx = UndefReads.back().second; } - LiveUnits.stepBackward(*I, *TRI); } } -- cgit v1.1