Set up the prologue and epilogue to be more like the manual and GCC output.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@14502 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/PowerPC/PowerPCRegisterInfo.cpp b/lib/Target/PowerPC/PowerPCRegisterInfo.cpp
index c7a1879e6d69d743b7a3a2144d445ba26d1f3b59..f96aee32d29a333af56e2e781b0c71101757df1b 100644 (file)
--- a/lib/Target/PowerPC/PowerPCRegisterInfo.cpp
+++ b/lib/Target/PowerPC/PowerPCRegisterInfo.cpp
@@ -202,7 +202,7 @@ void PowerPCRegisterInfo::emitPrologue(MachineFunction &MF) const {
     // Store the incoming LR so it is preserved across calls
     MI = BuildMI(PPC32::MFLR, 0, PPC32::R0);
     MBB.insert(MBBI, MI);
-    MI = BuildMI(PPC32::STW, 3).addReg(PPC32::R31).addSImm(-4)
+    MI = BuildMI(PPC32::STMW, 3).addReg(PPC32::R30).addSImm(-8)
            .addReg(PPC32::R1);
     MBB.insert(MBBI, MI);
     MI = BuildMI(PPC32::STW, 3).addReg(PPC32::R0).addSImm(8).addReg(PPC32::R1);
@@ -214,7 +214,7 @@ void PowerPCRegisterInfo::emitPrologue(MachineFunction &MF) const {
   
   // adjust stack pointer: r1 -= numbytes
   if (NumBytes) {
-    MI = BuildMI(PPC32::STWU, 2, PPC32::R1).addImm(-NumBytes).addReg(PPC32::R1);
+    MI = BuildMI(PPC32::STWU, 2, PPC32::R1).addImm(-80).addReg(PPC32::R1);
     MBB.insert(MBBI, MI);
   }
 }
@@ -230,21 +230,18 @@ void PowerPCRegisterInfo::emitEpilogue(MachineFunction &MF,
   // Get the number of bytes allocated from the FrameInfo...
   unsigned NumBytes = MFI->getStackSize();
 
-  // Read old LR from stack into R0
-  MI = BuildMI(PPC32::LWZ, 2, PPC32::R0).addSImm(8+NumBytes).addReg(PPC32::R1);
+  // Adjust stack pointer back
+  MI = BuildMI(PPC32::LWZ, 2, PPC32::R1).addImm(0).addReg(PPC32::R1);
   MBB.insert(MBBI, MI);
 
-  // Adjust stack pointer back: r1 += numbytes
-  if (NumBytes) {
-    MI = BuildMI(PPC32::ADDI, 2, PPC32::R1).addReg(PPC32::R1).addSImm(NumBytes);
-    MBB.insert(MBBI, MI);
-  }
- 
   // If we have calls, restore the LR value before we branch to it
   if (MFI->hasCalls()) {
+    // Read old LR from stack into R0
+    MI = BuildMI(PPC32::LWZ, 2, PPC32::R0).addSImm(8).addReg(PPC32::R1);
+    MBB.insert(MBBI, MI);
     MI = BuildMI(PPC32::MTLR, 1).addReg(PPC32::R0);
     MBB.insert(MBBI, MI);
-    MI = BuildMI(PPC32::LWZ, 2, PPC32::R31).addSImm(-4).addReg(PPC32::R1);
+    MI = BuildMI(PPC32::LMW, 2, PPC32::R30).addSImm(-8).addReg(PPC32::R1);
     MBB.insert(MBBI, MI);
   }
 }