From bc7f99a3ab802f4f5be6f3b0a97df03e6bfd3375 Mon Sep 17 00:00:00 2001 From: Michael Kuperstein Date: Wed, 12 Aug 2015 10:14:58 +0000 Subject: [X86] Allow x86 call frame optimization to fold more loads into pushes This abstracts away the test for "when can we fold across a MachineInstruction" into the the MI interface, and changes call-frame optimization use the same test the peephole optimizer users. Differential Revision: http://reviews.llvm.org/D11945 llvm-svn: 244729 --- llvm/lib/Target/X86/X86CallFrameOptimization.cpp | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) (limited to 'llvm/lib/Target') diff --git a/llvm/lib/Target/X86/X86CallFrameOptimization.cpp b/llvm/lib/Target/X86/X86CallFrameOptimization.cpp index 4fdb89631a9..dd33c2e54b8 100644 --- a/llvm/lib/Target/X86/X86CallFrameOptimization.cpp +++ b/llvm/lib/Target/X86/X86CallFrameOptimization.cpp @@ -528,13 +528,10 @@ MachineInstr *X86CallFrameOptimization::canFoldIntoRegPush( DefMI->getParent() != FrameSetup->getParent()) return nullptr; - // Now, make sure everything else up until the ADJCALLSTACK is a sequence - // of MOVs. To be less conservative would require duplicating a lot of the - // logic from PeepholeOptimizer. - // FIXME: A possibly better approach would be to teach the PeepholeOptimizer - // to be smarter about folding into pushes. + // Make sure we don't have any instructions between DefMI and the + // push that make folding the load illegal. for (auto I = DefMI; I != FrameSetup; ++I) - if (I->getOpcode() != X86::MOV32rm) + if (I->isLoadFoldBarrier()) return nullptr; return DefMI; -- cgit v1.2.3