From bd57186c763f9c47a6da570f56aceabd830e32a0 Mon Sep 17 00:00:00 2001 From: Michael Kuperstein Date: Sun, 1 Feb 2015 11:44:44 +0000 Subject: [X86] Convert esp-relative movs of function arguments to pushes, step 2 This moves the transformation introduced in r223757 into a separate MI pass. This allows it to cover many more cases (not only cases where there must be a reserved call frame), and perform rudimentary call folding. It still doesn't have a heuristic, so it is enabled only for optsize/minsize, with stack alignment <= 8, where it ought to be a fairly clear win. Differential Revision: http://reviews.llvm.org/D6789 llvm-svn: 227728 --- llvm/lib/CodeGen/PrologEpilogInserter.cpp | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) (limited to 'llvm/lib/CodeGen/PrologEpilogInserter.cpp') diff --git a/llvm/lib/CodeGen/PrologEpilogInserter.cpp b/llvm/lib/CodeGen/PrologEpilogInserter.cpp index 385e5a35afb..61407faaf32 100644 --- a/llvm/lib/CodeGen/PrologEpilogInserter.cpp +++ b/llvm/lib/CodeGen/PrologEpilogInserter.cpp @@ -703,7 +703,8 @@ void PEI::insertPrologEpilogCode(MachineFunction &Fn) { /// register references and actual offsets. /// void PEI::replaceFrameIndices(MachineFunction &Fn) { - if (!Fn.getFrameInfo()->hasStackObjects()) return; // Nothing to do? + const TargetFrameLowering &TFI = *Fn.getSubtarget().getFrameLowering(); + if (!TFI.needsFrameIndexResolution(Fn)) return; // Store SPAdj at exit of a basic block. SmallVector SPState; @@ -769,13 +770,6 @@ void PEI::replaceFrameIndices(MachineBasicBlock *BB, MachineFunction &Fn, continue; } - // If we are looking at a call sequence, we need to keep track of - // the SP adjustment made by each instruction in the sequence. - // This includes both the frame setup/destroy pseudos (handled above), - // as well as other instructions that have side effects w.r.t the SP. - if (InsideCallSequence) - SPAdj += TII.getSPAdjust(I); - MachineInstr *MI = I; bool DoIncr = true; for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { @@ -854,6 +848,16 @@ void PEI::replaceFrameIndices(MachineBasicBlock *BB, MachineFunction &Fn, break; } + // If we are looking at a call sequence, we need to keep track of + // the SP adjustment made by each instruction in the sequence. + // This includes both the frame setup/destroy pseudos (handled above), + // as well as other instructions that have side effects w.r.t the SP. + // Note that this must come after eliminateFrameIndex, because + // if I itself referred to a frame index, we shouldn't count its own + // adjustment. + if (MI && InsideCallSequence) + SPAdj += TII.getSPAdjust(MI); + if (DoIncr && I != BB->end()) ++I; // Update register states. -- cgit v1.2.3