Round up stack to multiple of alignment only if it's a leaf function without alloca.

llvm-svn: 33401

1 files changed, 7 insertions, 4 deletions

diff --git a/llvm/lib/Target/ARM/ARMRegisterInfo.cpp b/llvm/lib/Target/ARM/ARMRegisterInfo.cpp
index 767be023a5a..979cb513ef9 100644
--- a/llvm/lib/Target/ARM/ARMRegisterInfo.cpp
+++ b/llvm/lib/Target/ARM/ARMRegisterInfo.cpp
@@ -917,14 +917,17 @@ void ARMRegisterInfo::emitPrologue(MachineFunction &MF) const {
 
   // If necessary, add one more SUBri to account for the call frame
   // and/or local storage, alloca area.
-  if (MFI->hasCalls() && !hasFP(MF))
+  if (MFI->hasCalls() || MF.getFrameInfo()->hasVarSizedObjects()) {
     // We reserve argument space for call sites in the function immediately on
     // entry to the current function.  This eliminates the need for add/sub
     // brackets around call sites.
-    NumBytes += MFI->getMaxCallFrameSize();
+    if (!hasFP(MF))
+      NumBytes += MFI->getMaxCallFrameSize();
+
+    // Round the size to a multiple of the alignment.
+    NumBytes = (NumBytes+Align-1)/Align*Align;
+  }
 
-  // Round the size to a multiple of the alignment.
-  NumBytes = (NumBytes+Align-1)/Align*Align;
   MFI->setStackSize(NumBytes);
 
   // Determine starting offsets of spill areas.