Add methods to MipsFunctionInfo for initializing and accessing the stack frame

object for the global base register.

This is the first of a series of patches which implements long branch expansion
for MIPS.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158427 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/Mips/MipsMachineFunction.h b/lib/Target/Mips/MipsMachineFunction.h
index 04cb3f22b263af4881bbc5e8ab3a1a16c34f581b..b2232c6573cecf1e57678f34a79d0e4963cf8fd7 100644 (file)
--- a/lib/Target/Mips/MipsMachineFunction.h
+++ b/lib/Target/Mips/MipsMachineFunction.h
@@ -14,8 +14,11 @@
 #ifndef MIPS_MACHINE_FUNCTION_INFO_H
 #define MIPS_MACHINE_FUNCTION_INFO_H
 
+#include "MipsSubtarget.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/Target/TargetFrameLowering.h"
+#include "llvm/Target/TargetMachine.h"
 #include <utility>
 
 namespace llvm {
@@ -45,6 +48,7 @@ class MipsFunctionInfo : public MachineFunctionInfo {
   // OutArgFIRange: Range of indices of all frame objects created during call to
   //                LowerCall except for the frame object for restoring $gp.
   std::pair<int, int> InArgFIRange, OutArgFIRange;
+  int GlobalRegFI;
   mutable int DynAllocFI; // Frame index of dynamically allocated stack area.
   unsigned MaxCallFrameSize;
 
@@ -54,7 +58,7 @@ public:
   MipsFunctionInfo(MachineFunction& MF)
   : MF(MF), SRetReturnReg(0), GlobalBaseReg(0),
     VarArgsFrameIndex(0), InArgFIRange(std::make_pair(-1, 0)),
-    OutArgFIRange(std::make_pair(-1, 0)), DynAllocFI(0),
+    OutArgFIRange(std::make_pair(-1, 0)), GlobalRegFI(0), DynAllocFI(0),
     MaxCallFrameSize(0), EmitNOAT(false)
   {}
 
@@ -73,6 +77,24 @@ public:
     OutArgFIRange.second = LastFI;
   }
 
+  bool isGlobalRegFI(int FI) const {
+    return GlobalRegFI && (FI == GlobalRegFI);
+  }
+
+  int getGlobalRegFI() const {
+    return GlobalRegFI;
+  }
+
+  int initGlobalRegFI() {
+    const TargetMachine &TM = MF.getTarget();
+    unsigned RegSize = TM.getSubtarget<MipsSubtarget>().isABI_N64() ? 8 : 4;
+    int64_t StackAlignment = TM.getFrameLowering()->getStackAlignment();
+    uint64_t Offset = RoundUpToAlignment(MaxCallFrameSize, StackAlignment);
+
+    GlobalRegFI = MF.getFrameInfo()->CreateFixedObject(RegSize, Offset, true);
+    return GlobalRegFI;
+  }
+
   // The first call to this function creates a frame object for dynamically
   // allocated stack area.
   int getDynAllocFI() const {