[llvm-commits] CVS: llvm/lib/CodeGen/PrologEpilogInserter.cpp

[Evan Cheng]

Changes in directory llvm/lib/CodeGen:

PrologEpilogInserter.cpp updated: 1.65 -> 1.66
---
Log message:

PEI is now responsible for adding MaxCallFrameSize to frame size and align the stack. Each target can further adjust the frame size if necessary.

---
Diffs of the changes:  (+16 -1)

 PrologEpilogInserter.cpp |   17 ++++++++++++++++-
 1 files changed, 16 insertions(+), 1 deletion(-)


Index: llvm/lib/CodeGen/PrologEpilogInserter.cpp
diff -u llvm/lib/CodeGen/PrologEpilogInserter.cpp:1.65 llvm/lib/CodeGen/PrologEpilogInserter.cpp:1.66
--- llvm/lib/CodeGen/PrologEpilogInserter.cpp:1.65	Sat Jan 20 03:21:54 2007
+++ llvm/lib/CodeGen/PrologEpilogInserter.cpp	Tue Jan 23 03:36:03 2007
@@ -386,7 +386,22 @@
     }
   }
 
-  // Set the final value of the stack pointer...
+  // Round up the size to a multiple of the alignment, but only if there are
+  // calls or alloca's in the function.  This ensures that any calls to
+  // subroutines have their stack frames suitable aligned.
+  if (FFI->hasCalls() || FFI->hasVarSizedObjects()) {
+    // When we have no frame pointer, we reserve argument space for call sites
+    // in the function immediately on entry to the current function. This
+    // eliminates the need for add/sub sp brackets around call sites.
+    const MRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo();
+    if (!RegInfo->hasFP(Fn))
+      Offset += FFI->getMaxCallFrameSize();
+
+    unsigned AlignMask = TFI.getStackAlignment() - 1;
+    Offset = (Offset + AlignMask) & ~AlignMask;
+  }
+
+  // Update frame info to pretend that this is part of the stack...
   FFI->setStackSize(Offset+TFI.getOffsetOfLocalArea());
 
   // Remember the required stack alignment in case targets need it to perform