[llvm-commits] CVS: llvm/lib/Target/X86/X86RegisterInfo.cpp X86RegisterInfo.h

Misha Brukman brukman at cs.uiuc.edu
Wed Dec 4 17:58:00 PST 2002


Changes in directory llvm/lib/Target/X86:

X86RegisterInfo.cpp updated: 1.8 -> 1.9
X86RegisterInfo.h updated: 1.6 -> 1.7

---
Log message:

Implemented functions for emitting prologues and epilogues;
removed EBP from the list of callee-saved registers (it isn't one).


---
Diffs of the changes:

Index: llvm/lib/Target/X86/X86RegisterInfo.cpp
diff -u llvm/lib/Target/X86/X86RegisterInfo.cpp:1.8 llvm/lib/Target/X86/X86RegisterInfo.cpp:1.9
--- llvm/lib/Target/X86/X86RegisterInfo.cpp:1.8	Wed Dec  4 11:14:13 2002
+++ llvm/lib/Target/X86/X86RegisterInfo.cpp	Wed Dec  4 17:57:03 2002
@@ -58,7 +58,7 @@
 }
 
 const unsigned* X86RegisterInfo::getCalleeSaveRegs() const {
-  static const unsigned CalleeSaveRegs[] = { X86::ESI, X86::EDI, X86::EBX, X86::EBP,
+  static const unsigned CalleeSaveRegs[] = { X86::ESI, X86::EDI, X86::EBX,
                                              MRegisterInfo::NoRegister };
   return CalleeSaveRegs;
 }
@@ -68,4 +68,57 @@
   static const unsigned CallerSaveRegs[] = { X86::EAX, X86::ECX, X86::EDX,
                                              MRegisterInfo::NoRegister };
   return CallerSaveRegs;
+}
+
+MachineBasicBlock::iterator 
+X86RegisterInfo::emitPrologue(MachineBasicBlock *MBB,
+                              MachineBasicBlock::iterator MBBI,
+                              unsigned numBytes) const
+{
+  MachineInstr *MI;
+
+  // PUSH ebp
+  MI = BuildMI (X86::PUSHr32, 1).addReg(X86::EBP);
+  MBBI = ++(MBB->insert(MBBI, MI));
+
+  // MOV ebp, esp
+  MI = BuildMI (X86::MOVrr32, 2).addReg(X86::EBP).addReg(X86::ESP);
+  MBBI = ++(MBB->insert(MBBI, MI));  
+
+  // adjust stack pointer
+  MI  = BuildMI(X86::SUBri32, 2).addReg(X86::ESP).addZImm(numBytes);
+  MBBI = ++(MBB->insert(MBBI, MI));
+
+  // PUSH all callee-save registers
+  const unsigned* regs = getCalleeSaveRegs();
+  while (*regs) {
+    MI = BuildMI(X86::PUSHr32, 1).addReg(*regs);
+    MBBI = ++(MBB->insert(MBBI, MI));
+    ++regs;
+  }
+
+  return MBBI;
+}
+
+MachineBasicBlock::iterator
+X86RegisterInfo::emitEpilogue(MachineBasicBlock *MBB,
+                              MachineBasicBlock::iterator MBBI,
+                              unsigned numBytes) const
+{
+  MachineInstr *MI;
+
+  // POP all callee-save registers in REVERSE ORDER
+  static const unsigned regs[] = { X86::EBX, X86::EDI, X86::ESI,
+                                   MRegisterInfo::NoRegister };
+  unsigned idx = 0;
+  while (regs[idx]) {
+    MI = BuildMI(X86::POPr32, 1).addReg(regs[idx++]);
+    MBBI = ++(MBB->insert(MBBI, MI));
+  }
+  
+  // insert LEAVE
+  MI = BuildMI(X86::LEAVE, 0);
+  MBBI = ++(MBB->insert(MBBI, MI));
+  
+  return MBBI;
 }


Index: llvm/lib/Target/X86/X86RegisterInfo.h
diff -u llvm/lib/Target/X86/X86RegisterInfo.h:1.6 llvm/lib/Target/X86/X86RegisterInfo.h:1.7
--- llvm/lib/Target/X86/X86RegisterInfo.h:1.6	Wed Dec  4 11:14:13 2002
+++ llvm/lib/Target/X86/X86RegisterInfo.h	Wed Dec  4 17:57:03 2002
@@ -35,6 +35,14 @@
   const unsigned* getCalleeSaveRegs() const;
   const unsigned* getCallerSaveRegs() const;
 
+  MachineBasicBlock::iterator emitPrologue(MachineBasicBlock *MBB,
+                                           MachineBasicBlock::iterator MBBI,
+                                           unsigned numBytes) const;
+
+  MachineBasicBlock::iterator emitEpilogue(MachineBasicBlock *MBB,
+                                           MachineBasicBlock::iterator MBBI,
+                                           unsigned numBytes) const;
+
   /// Returns register class appropriate for input SSA register
   /// 
   const TargetRegisterClass *getClassForReg(unsigned Reg) const;





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