Pull in r227752 from upstream llvm trunk (by Michael Kuperstein):

  [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.

  (Re-commit of r227728)

  Differential Revision: http://reviews.llvm.org/D6789

This helps to get sys/boot/i386/boot2 below the required size again,
when optimizing with -Oz.

1 files changed, 5 insertions, 0 deletions

diff --git a/contrib/llvm/lib/Target/X86/X86TargetMachine.cpp b/contrib/llvm/lib/Target/X86/X86TargetMachine.cpp
index 5e6aa7d..1fc6b20 100644
--- a/contrib/llvm/lib/Target/X86/X86TargetMachine.cpp
+++ b/contrib/llvm/lib/Target/X86/X86TargetMachine.cpp
@@ -154,6 +154,7 @@ public:
   void addIRPasses() override;
   bool addInstSelector() override;
   bool addILPOpts() override;
+  void addPreRegAlloc() override;
   void addPostRegAlloc() override;
   void addPreEmitPass() override;
 };
@@ -187,6 +188,10 @@ bool X86PassConfig::addILPOpts() {
   return true;
 }
 
+void X86PassConfig::addPreRegAlloc() {
+  addPass(createX86CallFrameOptimization());
+}
+
 void X86PassConfig::addPostRegAlloc() {
   addPass(createX86FloatingPointStackifierPass());
 }