From 4e825336a0537c9e618d8011c9b1aad9a26e6dd8 Mon Sep 17 00:00:00 2001
From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Tue, 31 Oct 2006 13:03:26 +0000
Subject: [PATCH] add support for calling functions when the caller has
 variable sized objects

llvm-svn: 31312
---
 llvm/lib/Target/ARM/ARMRegisterInfo.cpp    | 20 +++++++++++++++++++-
 llvm/test/Regression/CodeGen/ARM/alloca.ll |  5 ++++-
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/Target/ARM/ARMRegisterInfo.cpp b/llvm/lib/Target/ARM/ARMRegisterInfo.cpp
index 885c5a7b9eb1..817c9faf4510 100644
--- a/llvm/lib/Target/ARM/ARMRegisterInfo.cpp
+++ b/llvm/lib/Target/ARM/ARMRegisterInfo.cpp
@@ -19,6 +19,8 @@
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineLocation.h"
 #include "llvm/Type.h"
+#include "llvm/Target/TargetFrameInfo.h"
+#include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/TargetOptions.h"
 #include "llvm/ADT/STLExtras.h"
 #include <iostream>
@@ -99,7 +101,23 @@ void ARMRegisterInfo::
 eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
                               MachineBasicBlock::iterator I) const {
   if (hasFP(MF)) {
-    assert(0);
+    MachineInstr *Old = I;
+    unsigned Amount = Old->getOperand(0).getImmedValue();
+    if (Amount != 0) {
+      unsigned Align = MF.getTarget().getFrameInfo()->getStackAlignment();
+      Amount = (Amount+Align-1)/Align*Align;
+
+      if (Old->getOpcode() == ARM::ADJCALLSTACKDOWN) {
+        // sub sp, sp, amount
+        BuildMI(MBB, I, ARM::SUB, 2, ARM::R13).addReg(ARM::R13).addImm(Amount)
+          .addImm(0).addImm(ARMShift::LSL);
+      } else {
+        // add sp, sp, amount
+        assert(Old->getOpcode() == ARM::ADJCALLSTACKUP);
+        BuildMI(MBB, I, ARM::ADD, 2, ARM::R13).addReg(ARM::R13).addImm(Amount)
+          .addImm(0).addImm(ARMShift::LSL);
+      }
+    }
   }
   MBB.erase(I);
 }
diff --git a/llvm/test/Regression/CodeGen/ARM/alloca.ll b/llvm/test/Regression/CodeGen/ARM/alloca.ll
index d5510d3e51f3..b77f234e1087 100644
--- a/llvm/test/Regression/CodeGen/ARM/alloca.ll
+++ b/llvm/test/Regression/CodeGen/ARM/alloca.ll
@@ -1,6 +1,9 @@
 ; RUN: llvm-as < %s | llc -march=arm
 void %f(uint %a) {
 entry:
-	%tmp1032 = alloca ubyte, uint %a
+	%tmp = alloca sbyte, uint %a
+	call void %g( sbyte* %tmp, uint %a, uint 1, uint 2, uint 3 )
 	ret void
 }
+
+declare void %g(sbyte*, uint, uint, uint, uint)