Compute correct frame sizes for SPARC v9 64-bit frames.

The save area is twice as big and there is no struct return slot. The
stack pointer is always 16-byte aligned (after adding the bias).

Also eliminate the stack adjustment instructions around calls when the
function has a reserved stack frame.

llvm-svn: 179083

1 files changed, 3 insertions, 2 deletions

diff --git a/llvm/lib/Target/Sparc/SparcISelLowering.cpp b/llvm/lib/Target/Sparc/SparcISelLowering.cpp
index eb01c5ef318..9dc5c1ffffd 100644
--- a/llvm/lib/Target/Sparc/SparcISelLowering.cpp
+++ b/llvm/lib/Target/Sparc/SparcISelLowering.cpp
@@ -912,8 +912,9 @@ SparcTargetLowering::LowerCall_64(TargetLowering::CallLoweringInfo &CLI,
 
   // Get the size of the outgoing arguments stack space requirement.
   // The stack offset computed by CC_Sparc64 includes all arguments.
-  // We always allocate space for 6 arguments in the prolog.
-  unsigned ArgsSize = std::max(6*8u, CCInfo.getNextStackOffset()) - 6*8u;
+  // Called functions expect 6 argument words to exist in the stack frame, used
+  // or not.
+  unsigned ArgsSize = std::max(6*8u, CCInfo.getNextStackOffset());
 
   // Keep stack frames 16-byte aligned.
   ArgsSize = RoundUpToAlignment(ArgsSize, 16);