[llvm-commits] CVS: llvm/lib/Target/PowerPC/PPCJITInfo.cpp PPCMachOWriter.cpp PPCRelocations.h

Nate Begeman natebegeman at mac.com
Fri Sep 8 15:42:25 PDT 2006



Changes in directory llvm/lib/Target/PowerPC:

PPCJITInfo.cpp updated: 1.28 -> 1.29
PPCMachOWriter.cpp updated: 1.3 -> 1.4
PPCRelocations.h updated: 1.9 -> 1.10
---
Log message:

First pass at supporting relocations.  Relocations are written correctly to
the file now, however the relocated address is currently wrong.  Fixing
that will require some deep pondering.


---
Diffs of the changes:  (+437 -370)

 PPCJITInfo.cpp     |  703 ++++++++++++++++++++++++++---------------------------
 PPCMachOWriter.cpp |   88 ++++++
 PPCRelocations.h   |   16 -
 3 files changed, 437 insertions(+), 370 deletions(-)


Index: llvm/lib/Target/PowerPC/PPCJITInfo.cpp
diff -u llvm/lib/Target/PowerPC/PPCJITInfo.cpp:1.28 llvm/lib/Target/PowerPC/PPCJITInfo.cpp:1.29
--- llvm/lib/Target/PowerPC/PPCJITInfo.cpp:1.28	Mon Aug 28 21:30:59 2006
+++ llvm/lib/Target/PowerPC/PPCJITInfo.cpp	Fri Sep  8 17:42:09 2006
@@ -1,353 +1,350 @@
-//===-- PPCJITInfo.cpp - Implement the JIT interfaces for the PowerPC -----===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file implements the JIT interfaces for the 32-bit PowerPC target.
-//
-//===----------------------------------------------------------------------===//
-
-#define DEBUG_TYPE "jit"
-#include "PPCJITInfo.h"
-#include "PPCRelocations.h"
-#include "llvm/CodeGen/MachineCodeEmitter.h"
-#include "llvm/Config/alloca.h"
-#include "llvm/Support/Debug.h"
-#include <set>
-#include <iostream>
-using namespace llvm;
-
-static TargetJITInfo::JITCompilerFn JITCompilerFunction;
-
-#define BUILD_ADDIS(RD,RS,IMM16) \
-  ((15 << 26) | ((RD) << 21) | ((RS) << 16) | ((IMM16) & 65535))
-#define BUILD_ORI(RD,RS,UIMM16) \
-  ((24 << 26) | ((RS) << 21) | ((RD) << 16) | ((UIMM16) & 65535))
-#define BUILD_ORIS(RD,RS,UIMM16) \
-  ((25 << 26) | ((RS) << 21) | ((RD) << 16) | ((UIMM16) & 65535))
-#define BUILD_RLDICR(RD,RS,SH,ME) \
-  ((30 << 26) | ((RS) << 21) | ((RD) << 16) | (((SH) & 31) << 11) | \
-   (((ME) & 63) << 6) | (1 << 3) | (((SH) >> 5) & 1))
-#define BUILD_MTSPR(RS,SPR)      \
-  ((31 << 26) | ((RS) << 21) | ((SPR) << 16) | (467 << 1))
-#define BUILD_BCCTRx(BO,BI,LINK) \
-  ((19 << 26) | ((BO) << 21) | ((BI) << 16) | (528 << 1) | ((LINK) & 1))
-#define BUILD_B(TARGET, LINK) \
-  ((18 << 26) | (((TARGET) & 0x00FFFFFF) << 2) | ((LINK) & 1))
-
-// Pseudo-ops
-#define BUILD_LIS(RD,IMM16)    BUILD_ADDIS(RD,0,IMM16)
-#define BUILD_SLDI(RD,RS,IMM6) BUILD_RLDICR(RD,RS,IMM6,63-IMM6)
-#define BUILD_MTCTR(RS)        BUILD_MTSPR(RS,9)
-#define BUILD_BCTR(LINK)       BUILD_BCCTRx(20,0,LINK)
-
-static void EmitBranchToAt(uint64_t At, uint64_t To, bool isCall, bool is64Bit){
-  intptr_t Offset = ((intptr_t)To - (intptr_t)At) >> 2;
-  unsigned *AtI = (unsigned*)(intptr_t)At;
-
-  if (Offset >= -(1 << 23) && Offset < (1 << 23)) {   // In range?
-    AtI[0] = BUILD_B(Offset, isCall);     // b/bl target
-  } else if (!is64Bit) {
-    AtI[0] = BUILD_LIS(12, To >> 16);     // lis r12, hi16(address)
-    AtI[1] = BUILD_ORI(12, 12, To);       // ori r12, r12, lo16(address)
-    AtI[2] = BUILD_MTCTR(12);             // mtctr r12
-    AtI[3] = BUILD_BCTR(isCall);          // bctr/bctrl
-  } else {
-    AtI[0] = BUILD_LIS(12, To >> 48);      // lis r12, hi16(address)
-    AtI[1] = BUILD_ORI(12, 12, To >> 32);  // ori r12, r12, lo16(address)
-    AtI[2] = BUILD_SLDI(12, 12, 32);       // sldi r12, r12, 32
-    AtI[3] = BUILD_ORIS(12, 12, To >> 16); // oris r12, r12, hi16(address)
-    AtI[4] = BUILD_ORI(12, 12, To);        // ori r12, r12, lo16(address)
-    AtI[5] = BUILD_MTCTR(12);              // mtctr r12
-    AtI[6] = BUILD_BCTR(isCall);           // bctr/bctrl
-  }
-}
-
-extern "C" void PPC32CompilationCallback();
-extern "C" void PPC64CompilationCallback();
-
-#if (defined(__POWERPC__) || defined (__ppc__) || defined(_POWER)) && !defined(__ppc64__)
-// CompilationCallback stub - We can't use a C function with inline assembly in
-// it, because we the prolog/epilog inserted by GCC won't work for us.  Instead,
-// write our own wrapper, which does things our way, so we have complete control
-// over register saving and restoring.
-asm(
-    ".text\n"
-    ".align 2\n"
-    ".globl _PPC32CompilationCallback\n"
-"_PPC32CompilationCallback:\n"
-    // Make space for 8 ints r[3-10] and 13 doubles f[1-13] and the 
-    // FIXME: need to save v[0-19] for altivec?
-    // FIXME: could shrink frame
-    // Set up a proper stack frame
-    "stwu r1, -208(r1)\n"
-    "mflr r0\n"
-    "stw r0,  216(r1)\n"
-    // Save all int arg registers
-    "stw r10, 204(r1)\n"    "stw r9,  200(r1)\n"
-    "stw r8,  196(r1)\n"    "stw r7,  192(r1)\n"
-    "stw r6,  188(r1)\n"    "stw r5,  184(r1)\n"
-    "stw r4,  180(r1)\n"    "stw r3,  176(r1)\n"
-    // Save all call-clobbered FP regs.
-    "stfd f13, 168(r1)\n"   "stfd f12, 160(r1)\n"
-    "stfd f11, 152(r1)\n"   "stfd f10, 144(r1)\n"
-    "stfd f9,  136(r1)\n"   "stfd f8,  128(r1)\n"
-    "stfd f7,  120(r1)\n"   "stfd f6,  112(r1)\n"
-    "stfd f5,  104(r1)\n"   "stfd f4,   96(r1)\n"
-    "stfd f3,   88(r1)\n"   "stfd f2,   80(r1)\n"
-    "stfd f1,   72(r1)\n"
-    // Arguments to Compilation Callback:
-    // r3 - our lr (address of the call instruction in stub plus 4)
-    // r4 - stub's lr (address of instruction that called the stub plus 4)
-    "mr   r3, r0\n"
-    "lwz  r2, 208(r1)\n" // stub's frame
-    "lwz  r4, 8(r2)\n" // stub's lr
-    "li   r5, 0\n"       // 0 == 32 bit
-    "bl _PPCCompilationCallbackC\n"
-    "mtctr r3\n"
-    // Restore all int arg registers
-    "lwz r10, 204(r1)\n"    "lwz r9,  200(r1)\n"
-    "lwz r8,  196(r1)\n"    "lwz r7,  192(r1)\n"
-    "lwz r6,  188(r1)\n"    "lwz r5,  184(r1)\n"
-    "lwz r4,  180(r1)\n"    "lwz r3,  176(r1)\n"
-    // Restore all FP arg registers
-    "lfd f13, 168(r1)\n"    "lfd f12, 160(r1)\n"
-    "lfd f11, 152(r1)\n"    "lfd f10, 144(r1)\n"
-    "lfd f9,  136(r1)\n"    "lfd f8,  128(r1)\n"
-    "lfd f7,  120(r1)\n"    "lfd f6,  112(r1)\n"
-    "lfd f5,  104(r1)\n"    "lfd f4,   96(r1)\n"
-    "lfd f3,   88(r1)\n"    "lfd f2,   80(r1)\n"
-    "lfd f1,   72(r1)\n"
-    // Pop 3 frames off the stack and branch to target
-    "lwz  r1, 208(r1)\n"
-    "lwz  r2, 8(r1)\n"
-    "mtlr r2\n"
-    "bctr\n"
-    );
-#else
-void PPC32CompilationCallback() {
-  assert(0 && "This is not a power pc, you can't execute this!");
-  abort();
-}
-#endif
-
-#if (defined(__POWERPC__) || defined (__ppc__) || defined(_POWER)) && defined(__ppc64__)
-asm(
-    ".text\n"
-    ".align 2\n"
-    ".globl _PPC64CompilationCallback\n"
-"_PPC64CompilationCallback:\n"
-    // Make space for 8 ints r[3-10] and 13 doubles f[1-13] and the 
-    // FIXME: need to save v[0-19] for altivec?
-    // Set up a proper stack frame
-    "stdu r1, -208(r1)\n"
-    "mflr r0\n"
-    "std r0,  224(r1)\n"
-    // Save all int arg registers
-    "std r10, 200(r1)\n"    "std r9,  192(r1)\n"
-    "std r8,  184(r1)\n"    "std r7,  176(r1)\n"
-    "std r6,  168(r1)\n"    "std r5,  160(r1)\n"
-    "std r4,  152(r1)\n"    "std r3,  144(r1)\n"
-    // Save all call-clobbered FP regs.
-    "stfd f13, 136(r1)\n"   "stfd f12, 128(r1)\n"
-    "stfd f11, 120(r1)\n"   "stfd f10, 112(r1)\n"
-    "stfd f9,  104(r1)\n"   "stfd f8,   96(r1)\n"
-    "stfd f7,   88(r1)\n"   "stfd f6,   80(r1)\n"
-    "stfd f5,   72(r1)\n"   "stfd f4,   64(r1)\n"
-    "stfd f3,   56(r1)\n"   "stfd f2,   48(r1)\n"
-    "stfd f1,   40(r1)\n"
-    // Arguments to Compilation Callback:
-    // r3 - our lr (address of the call instruction in stub plus 4)
-    // r4 - stub's lr (address of instruction that called the stub plus 4)
-    "mr   r3, r0\n"
-    "ld   r2, 208(r1)\n" // stub's frame
-    "ld   r4, 16(r2)\n"  // stub's lr
-    "li   r5, 1\n"       // 1 == 64 bit
-    "bl _PPCCompilationCallbackC\n"
-    "mtctr r3\n"
-    // Restore all int arg registers
-    "ld r10, 200(r1)\n"    "ld r9,  192(r1)\n"
-    "ld r8,  184(r1)\n"    "ld r7,  176(r1)\n"
-    "ld r6,  168(r1)\n"    "ld r5,  160(r1)\n"
-    "ld r4,  152(r1)\n"    "ld r3,  144(r1)\n"
-    // Restore all FP arg registers
-    "lfd f13, 136(r1)\n"    "lfd f12, 128(r1)\n"
-    "lfd f11, 120(r1)\n"    "lfd f10, 112(r1)\n"
-    "lfd f9,  104(r1)\n"    "lfd f8,   96(r1)\n"
-    "lfd f7,   88(r1)\n"    "lfd f6,   80(r1)\n"
-    "lfd f5,   72(r1)\n"    "lfd f4,   64(r1)\n"
-    "lfd f3,   56(r1)\n"    "lfd f2,   48(r1)\n"
-    "lfd f1,   40(r1)\n"
-    // Pop 3 frames off the stack and branch to target
-    "ld  r1, 208(r1)\n"
-    "ld  r2, 16(r1)\n"
-    "mtlr r2\n"
-    "bctr\n"
-    );
-#else
-void PPC64CompilationCallback() {
-  assert(0 && "This is not a power pc, you can't execute this!");
-  abort();
-}
-#endif
-
-extern "C" void *PPCCompilationCallbackC(unsigned *StubCallAddrPlus4,
-                                         unsigned *OrigCallAddrPlus4,
-                                         bool is64Bit) {
-  // Adjust the pointer to the address of the call instruction in the stub
-  // emitted by emitFunctionStub, rather than the instruction after it.
-  unsigned *StubCallAddr = StubCallAddrPlus4 - 1;
-  unsigned *OrigCallAddr = OrigCallAddrPlus4 - 1;
-
-  void *Target = JITCompilerFunction(StubCallAddr);
-
-  // Check to see if *OrigCallAddr is a 'bl' instruction, and if we can rewrite
-  // it to branch directly to the destination.  If so, rewrite it so it does not
-  // need to go through the stub anymore.
-  unsigned OrigCallInst = *OrigCallAddr;
-  if ((OrigCallInst >> 26) == 18) {     // Direct call.
-    intptr_t Offset = ((intptr_t)Target - (intptr_t)OrigCallAddr) >> 2;
-    
-    if (Offset >= -(1 << 23) && Offset < (1 << 23)) {   // In range?
-      // Clear the original target out.
-      OrigCallInst &= (63 << 26) | 3;
-      // Fill in the new target.
-      OrigCallInst |= (Offset & ((1 << 24)-1)) << 2;
-      // Replace the call.
-      *OrigCallAddr = OrigCallInst;
-    }
-  }
-
-  // Assert that we are coming from a stub that was created with our
-  // emitFunctionStub.
-  if ((*StubCallAddr >> 26) == 18)
-    StubCallAddr -= 3;
-  else {
-  assert((*StubCallAddr >> 26) == 19 && "Call in stub is not indirect!");
-    StubCallAddr -= is64Bit ? 9 : 6;
-  }
-
-  // Rewrite the stub with an unconditional branch to the target, for any users
-  // who took the address of the stub.
-  EmitBranchToAt((intptr_t)StubCallAddr, (intptr_t)Target, false, is64Bit);
-
-  // Put the address of the target function to call and the address to return to
-  // after calling the target function in a place that is easy to get on the
-  // stack after we restore all regs.
-  return Target;
-}
-
-
-
-TargetJITInfo::LazyResolverFn
-PPCJITInfo::getLazyResolverFunction(JITCompilerFn Fn) {
-  JITCompilerFunction = Fn;
-  return is64Bit ? PPC64CompilationCallback : PPC32CompilationCallback;
-}
-
-void *PPCJITInfo::emitFunctionStub(void *Fn, MachineCodeEmitter &MCE) {
-  // If this is just a call to an external function, emit a branch instead of a
-  // call.  The code is the same except for one bit of the last instruction.
-  if (Fn != (void*)(intptr_t)PPC32CompilationCallback && 
-      Fn != (void*)(intptr_t)PPC64CompilationCallback) {
-    MCE.startFunctionStub(7*4);
-    intptr_t Addr = (intptr_t)MCE.getCurrentPCValue();
-    MCE.emitWordBE(0);
-    MCE.emitWordBE(0);
-    MCE.emitWordBE(0);
-    MCE.emitWordBE(0);
-    MCE.emitWordBE(0);
-    MCE.emitWordBE(0);
-    MCE.emitWordBE(0);
-    EmitBranchToAt(Addr, (intptr_t)Fn, false, is64Bit);
-    return MCE.finishFunctionStub(0);
-  }
-
-  MCE.startFunctionStub(10*4);
-  if (is64Bit) {
-    MCE.emitWordBE(0xf821ffb1);     // stdu r1,-80(r1)
-    MCE.emitWordBE(0x7d6802a6);     // mflr r11
-    MCE.emitWordBE(0xf9610060);     // std r11, 96(r1)
-  } else {
-    MCE.emitWordBE(0x9421ffe0);     // stwu r1,-32(r1)
-    MCE.emitWordBE(0x7d6802a6);     // mflr r11
-    MCE.emitWordBE(0x91610028);     // stw r11, 40(r1)
-  }
-  intptr_t Addr = (intptr_t)MCE.getCurrentPCValue();
-  MCE.emitWordBE(0);
-  MCE.emitWordBE(0);
-  MCE.emitWordBE(0);
-  MCE.emitWordBE(0);
-  MCE.emitWordBE(0);
-  MCE.emitWordBE(0);
-  MCE.emitWordBE(0);
-  EmitBranchToAt(Addr, (intptr_t)Fn, true, is64Bit);
-  return MCE.finishFunctionStub(0);
-}
-
-
-void PPCJITInfo::relocate(void *Function, MachineRelocation *MR,
-                          unsigned NumRelocs, unsigned char* GOTBase) {
-  for (unsigned i = 0; i != NumRelocs; ++i, ++MR) {
-    unsigned *RelocPos = (unsigned*)Function + MR->getMachineCodeOffset()/4;
-    intptr_t ResultPtr = (intptr_t)MR->getResultPointer();
-    switch ((PPC::RelocationType)MR->getRelocationType()) {
-    default: assert(0 && "Unknown relocation type!");
-    case PPC::reloc_pcrel_bx:
-      // PC-relative relocation for b and bl instructions.
-      ResultPtr = (ResultPtr-(intptr_t)RelocPos) >> 2;
-      assert(ResultPtr >= -(1 << 23) && ResultPtr < (1 << 23) &&
-             "Relocation out of range!");
-      *RelocPos |= (ResultPtr & ((1 << 24)-1))  << 2;
-      break;
-    case PPC::reloc_pcrel_bcx:
-      // PC-relative relocation for BLT,BLE,BEQ,BGE,BGT,BNE, or other
-      // bcx instructions.
-      ResultPtr = (ResultPtr-(intptr_t)RelocPos) >> 2;
-      assert(ResultPtr >= -(1 << 13) && ResultPtr < (1 << 13) &&
-             "Relocation out of range!");
-      *RelocPos |= (ResultPtr & ((1 << 14)-1))  << 2;
-      break;
-    case PPC::reloc_absolute_ptr_high: // Pointer relocations.
-    case PPC::reloc_absolute_ptr_low:
-    case PPC::reloc_absolute_high:     // high bits of ref -> low 16 of instr
-    case PPC::reloc_absolute_low: {    // low bits of ref  -> low 16 of instr
-      ResultPtr += MR->getConstantVal();
-
-      // If this is a high-part access, get the high-part.
-      if (MR->getRelocationType() == PPC::reloc_absolute_high ||
-          MR->getRelocationType() == PPC::reloc_absolute_ptr_high) {
-        // If the low part will have a carry (really a borrow) from the low
-        // 16-bits into the high 16, add a bit to borrow from.
-        if (((int)ResultPtr << 16) < 0)
-          ResultPtr += 1 << 16;
-        ResultPtr >>= 16;
-      }
-
-      // Do the addition then mask, so the addition does not overflow the 16-bit
-      // immediate section of the instruction.
-      unsigned LowBits  = (*RelocPos + ResultPtr) & 65535;
-      unsigned HighBits = *RelocPos & ~65535;
-      *RelocPos = LowBits | HighBits;  // Slam into low 16-bits
-      break;
-    }
-    case PPC::reloc_absolute_low_ix: {  // low bits of ref  -> low 14 of instr
-      ResultPtr += MR->getConstantVal();
-      // Do the addition then mask, so the addition does not overflow the 16-bit
-      // immediate section of the instruction.
-      unsigned LowBits  = (*RelocPos + ResultPtr) & 0xFFFC;
-      unsigned HighBits = *RelocPos & 0xFFFF0003;
-      *RelocPos = LowBits | HighBits;  // Slam into low 14-bits.
-      break;
-    }
-    }
-  }
-}
-
-void PPCJITInfo::replaceMachineCodeForFunction(void *Old, void *New) {
-  EmitBranchToAt((intptr_t)Old, (intptr_t)New, false, is64Bit);
-}
+//===-- PPCJITInfo.cpp - Implement the JIT interfaces for the PowerPC -----===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the JIT interfaces for the 32-bit PowerPC target.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "jit"
+#include "PPCJITInfo.h"
+#include "PPCRelocations.h"
+#include "llvm/CodeGen/MachineCodeEmitter.h"
+#include "llvm/Config/alloca.h"
+#include "llvm/Support/Debug.h"
+#include <set>
+#include <iostream>
+using namespace llvm;
+
+static TargetJITInfo::JITCompilerFn JITCompilerFunction;
+
+#define BUILD_ADDIS(RD,RS,IMM16) \
+  ((15 << 26) | ((RD) << 21) | ((RS) << 16) | ((IMM16) & 65535))
+#define BUILD_ORI(RD,RS,UIMM16) \
+  ((24 << 26) | ((RS) << 21) | ((RD) << 16) | ((UIMM16) & 65535))
+#define BUILD_ORIS(RD,RS,UIMM16) \
+  ((25 << 26) | ((RS) << 21) | ((RD) << 16) | ((UIMM16) & 65535))
+#define BUILD_RLDICR(RD,RS,SH,ME) \
+  ((30 << 26) | ((RS) << 21) | ((RD) << 16) | (((SH) & 31) << 11) | \
+   (((ME) & 63) << 6) | (1 << 3) | (((SH) >> 5) & 1))
+#define BUILD_MTSPR(RS,SPR)      \
+  ((31 << 26) | ((RS) << 21) | ((SPR) << 16) | (467 << 1))
+#define BUILD_BCCTRx(BO,BI,LINK) \
+  ((19 << 26) | ((BO) << 21) | ((BI) << 16) | (528 << 1) | ((LINK) & 1))
+#define BUILD_B(TARGET, LINK) \
+  ((18 << 26) | (((TARGET) & 0x00FFFFFF) << 2) | ((LINK) & 1))
+
+// Pseudo-ops
+#define BUILD_LIS(RD,IMM16)    BUILD_ADDIS(RD,0,IMM16)
+#define BUILD_SLDI(RD,RS,IMM6) BUILD_RLDICR(RD,RS,IMM6,63-IMM6)
+#define BUILD_MTCTR(RS)        BUILD_MTSPR(RS,9)
+#define BUILD_BCTR(LINK)       BUILD_BCCTRx(20,0,LINK)
+
+static void EmitBranchToAt(uint64_t At, uint64_t To, bool isCall, bool is64Bit){
+  intptr_t Offset = ((intptr_t)To - (intptr_t)At) >> 2;
+  unsigned *AtI = (unsigned*)(intptr_t)At;
+
+  if (Offset >= -(1 << 23) && Offset < (1 << 23)) {   // In range?
+    AtI[0] = BUILD_B(Offset, isCall);     // b/bl target
+  } else if (!is64Bit) {
+    AtI[0] = BUILD_LIS(12, To >> 16);     // lis r12, hi16(address)
+    AtI[1] = BUILD_ORI(12, 12, To);       // ori r12, r12, lo16(address)
+    AtI[2] = BUILD_MTCTR(12);             // mtctr r12
+    AtI[3] = BUILD_BCTR(isCall);          // bctr/bctrl
+  } else {
+    AtI[0] = BUILD_LIS(12, To >> 48);      // lis r12, hi16(address)
+    AtI[1] = BUILD_ORI(12, 12, To >> 32);  // ori r12, r12, lo16(address)
+    AtI[2] = BUILD_SLDI(12, 12, 32);       // sldi r12, r12, 32
+    AtI[3] = BUILD_ORIS(12, 12, To >> 16); // oris r12, r12, hi16(address)
+    AtI[4] = BUILD_ORI(12, 12, To);        // ori r12, r12, lo16(address)
+    AtI[5] = BUILD_MTCTR(12);              // mtctr r12
+    AtI[6] = BUILD_BCTR(isCall);           // bctr/bctrl
+  }
+}
+
+extern "C" void PPC32CompilationCallback();
+extern "C" void PPC64CompilationCallback();
+
+#if (defined(__POWERPC__) || defined (__ppc__) || defined(_POWER)) && !defined(__ppc64__)
+// CompilationCallback stub - We can't use a C function with inline assembly in
+// it, because we the prolog/epilog inserted by GCC won't work for us.  Instead,
+// write our own wrapper, which does things our way, so we have complete control
+// over register saving and restoring.
+asm(
+    ".text\n"
+    ".align 2\n"
+    ".globl _PPC32CompilationCallback\n"
+"_PPC32CompilationCallback:\n"
+    // Make space for 8 ints r[3-10] and 13 doubles f[1-13] and the 
+    // FIXME: need to save v[0-19] for altivec?
+    // FIXME: could shrink frame
+    // Set up a proper stack frame
+    "stwu r1, -208(r1)\n"
+    "mflr r0\n"
+    "stw r0,  216(r1)\n"
+    // Save all int arg registers
+    "stw r10, 204(r1)\n"    "stw r9,  200(r1)\n"
+    "stw r8,  196(r1)\n"    "stw r7,  192(r1)\n"
+    "stw r6,  188(r1)\n"    "stw r5,  184(r1)\n"
+    "stw r4,  180(r1)\n"    "stw r3,  176(r1)\n"
+    // Save all call-clobbered FP regs.
+    "stfd f13, 168(r1)\n"   "stfd f12, 160(r1)\n"
+    "stfd f11, 152(r1)\n"   "stfd f10, 144(r1)\n"
+    "stfd f9,  136(r1)\n"   "stfd f8,  128(r1)\n"
+    "stfd f7,  120(r1)\n"   "stfd f6,  112(r1)\n"
+    "stfd f5,  104(r1)\n"   "stfd f4,   96(r1)\n"
+    "stfd f3,   88(r1)\n"   "stfd f2,   80(r1)\n"
+    "stfd f1,   72(r1)\n"
+    // Arguments to Compilation Callback:
+    // r3 - our lr (address of the call instruction in stub plus 4)
+    // r4 - stub's lr (address of instruction that called the stub plus 4)
+    "mr   r3, r0\n"
+    "lwz  r2, 208(r1)\n" // stub's frame
+    "lwz  r4, 8(r2)\n" // stub's lr
+    "li   r5, 0\n"       // 0 == 32 bit
+    "bl _PPCCompilationCallbackC\n"
+    "mtctr r3\n"
+    // Restore all int arg registers
+    "lwz r10, 204(r1)\n"    "lwz r9,  200(r1)\n"
+    "lwz r8,  196(r1)\n"    "lwz r7,  192(r1)\n"
+    "lwz r6,  188(r1)\n"    "lwz r5,  184(r1)\n"
+    "lwz r4,  180(r1)\n"    "lwz r3,  176(r1)\n"
+    // Restore all FP arg registers
+    "lfd f13, 168(r1)\n"    "lfd f12, 160(r1)\n"
+    "lfd f11, 152(r1)\n"    "lfd f10, 144(r1)\n"
+    "lfd f9,  136(r1)\n"    "lfd f8,  128(r1)\n"
+    "lfd f7,  120(r1)\n"    "lfd f6,  112(r1)\n"
+    "lfd f5,  104(r1)\n"    "lfd f4,   96(r1)\n"
+    "lfd f3,   88(r1)\n"    "lfd f2,   80(r1)\n"
+    "lfd f1,   72(r1)\n"
+    // Pop 3 frames off the stack and branch to target
+    "lwz  r1, 208(r1)\n"
+    "lwz  r2, 8(r1)\n"
+    "mtlr r2\n"
+    "bctr\n"
+    );
+#else
+void PPC32CompilationCallback() {
+  assert(0 && "This is not a power pc, you can't execute this!");
+  abort();
+}
+#endif
+
+#if (defined(__POWERPC__) || defined (__ppc__) || defined(_POWER)) && defined(__ppc64__)
+asm(
+    ".text\n"
+    ".align 2\n"
+    ".globl _PPC64CompilationCallback\n"
+"_PPC64CompilationCallback:\n"
+    // Make space for 8 ints r[3-10] and 13 doubles f[1-13] and the 
+    // FIXME: need to save v[0-19] for altivec?
+    // Set up a proper stack frame
+    "stdu r1, -208(r1)\n"
+    "mflr r0\n"
+    "std r0,  224(r1)\n"
+    // Save all int arg registers
+    "std r10, 200(r1)\n"    "std r9,  192(r1)\n"
+    "std r8,  184(r1)\n"    "std r7,  176(r1)\n"
+    "std r6,  168(r1)\n"    "std r5,  160(r1)\n"
+    "std r4,  152(r1)\n"    "std r3,  144(r1)\n"
+    // Save all call-clobbered FP regs.
+    "stfd f13, 136(r1)\n"   "stfd f12, 128(r1)\n"
+    "stfd f11, 120(r1)\n"   "stfd f10, 112(r1)\n"
+    "stfd f9,  104(r1)\n"   "stfd f8,   96(r1)\n"
+    "stfd f7,   88(r1)\n"   "stfd f6,   80(r1)\n"
+    "stfd f5,   72(r1)\n"   "stfd f4,   64(r1)\n"
+    "stfd f3,   56(r1)\n"   "stfd f2,   48(r1)\n"
+    "stfd f1,   40(r1)\n"
+    // Arguments to Compilation Callback:
+    // r3 - our lr (address of the call instruction in stub plus 4)
+    // r4 - stub's lr (address of instruction that called the stub plus 4)
+    "mr   r3, r0\n"
+    "ld   r2, 208(r1)\n" // stub's frame
+    "ld   r4, 16(r2)\n"  // stub's lr
+    "li   r5, 1\n"       // 1 == 64 bit
+    "bl _PPCCompilationCallbackC\n"
+    "mtctr r3\n"
+    // Restore all int arg registers
+    "ld r10, 200(r1)\n"    "ld r9,  192(r1)\n"
+    "ld r8,  184(r1)\n"    "ld r7,  176(r1)\n"
+    "ld r6,  168(r1)\n"    "ld r5,  160(r1)\n"
+    "ld r4,  152(r1)\n"    "ld r3,  144(r1)\n"
+    // Restore all FP arg registers
+    "lfd f13, 136(r1)\n"    "lfd f12, 128(r1)\n"
+    "lfd f11, 120(r1)\n"    "lfd f10, 112(r1)\n"
+    "lfd f9,  104(r1)\n"    "lfd f8,   96(r1)\n"
+    "lfd f7,   88(r1)\n"    "lfd f6,   80(r1)\n"
+    "lfd f5,   72(r1)\n"    "lfd f4,   64(r1)\n"
+    "lfd f3,   56(r1)\n"    "lfd f2,   48(r1)\n"
+    "lfd f1,   40(r1)\n"
+    // Pop 3 frames off the stack and branch to target
+    "ld  r1, 208(r1)\n"
+    "ld  r2, 16(r1)\n"
+    "mtlr r2\n"
+    "bctr\n"
+    );
+#else
+void PPC64CompilationCallback() {
+  assert(0 && "This is not a power pc, you can't execute this!");
+  abort();
+}
+#endif
+
+extern "C" void *PPCCompilationCallbackC(unsigned *StubCallAddrPlus4,
+                                         unsigned *OrigCallAddrPlus4,
+                                         bool is64Bit) {
+  // Adjust the pointer to the address of the call instruction in the stub
+  // emitted by emitFunctionStub, rather than the instruction after it.
+  unsigned *StubCallAddr = StubCallAddrPlus4 - 1;
+  unsigned *OrigCallAddr = OrigCallAddrPlus4 - 1;
+
+  void *Target = JITCompilerFunction(StubCallAddr);
+
+  // Check to see if *OrigCallAddr is a 'bl' instruction, and if we can rewrite
+  // it to branch directly to the destination.  If so, rewrite it so it does not
+  // need to go through the stub anymore.
+  unsigned OrigCallInst = *OrigCallAddr;
+  if ((OrigCallInst >> 26) == 18) {     // Direct call.
+    intptr_t Offset = ((intptr_t)Target - (intptr_t)OrigCallAddr) >> 2;
+    
+    if (Offset >= -(1 << 23) && Offset < (1 << 23)) {   // In range?
+      // Clear the original target out.
+      OrigCallInst &= (63 << 26) | 3;
+      // Fill in the new target.
+      OrigCallInst |= (Offset & ((1 << 24)-1)) << 2;
+      // Replace the call.
+      *OrigCallAddr = OrigCallInst;
+    }
+  }
+
+  // Assert that we are coming from a stub that was created with our
+  // emitFunctionStub.
+  if ((*StubCallAddr >> 26) == 18)
+    StubCallAddr -= 3;
+  else {
+  assert((*StubCallAddr >> 26) == 19 && "Call in stub is not indirect!");
+    StubCallAddr -= is64Bit ? 9 : 6;
+  }
+
+  // Rewrite the stub with an unconditional branch to the target, for any users
+  // who took the address of the stub.
+  EmitBranchToAt((intptr_t)StubCallAddr, (intptr_t)Target, false, is64Bit);
+
+  // Put the address of the target function to call and the address to return to
+  // after calling the target function in a place that is easy to get on the
+  // stack after we restore all regs.
+  return Target;
+}
+
+
+
+TargetJITInfo::LazyResolverFn
+PPCJITInfo::getLazyResolverFunction(JITCompilerFn Fn) {
+  JITCompilerFunction = Fn;
+  return is64Bit ? PPC64CompilationCallback : PPC32CompilationCallback;
+}
+
+void *PPCJITInfo::emitFunctionStub(void *Fn, MachineCodeEmitter &MCE) {
+  // If this is just a call to an external function, emit a branch instead of a
+  // call.  The code is the same except for one bit of the last instruction.
+  if (Fn != (void*)(intptr_t)PPC32CompilationCallback && 
+      Fn != (void*)(intptr_t)PPC64CompilationCallback) {
+    MCE.startFunctionStub(7*4);
+    intptr_t Addr = (intptr_t)MCE.getCurrentPCValue();
+    MCE.emitWordBE(0);
+    MCE.emitWordBE(0);
+    MCE.emitWordBE(0);
+    MCE.emitWordBE(0);
+    MCE.emitWordBE(0);
+    MCE.emitWordBE(0);
+    MCE.emitWordBE(0);
+    EmitBranchToAt(Addr, (intptr_t)Fn, false, is64Bit);
+    return MCE.finishFunctionStub(0);
+  }
+
+  MCE.startFunctionStub(10*4);
+  if (is64Bit) {
+    MCE.emitWordBE(0xf821ffb1);     // stdu r1,-80(r1)
+    MCE.emitWordBE(0x7d6802a6);     // mflr r11
+    MCE.emitWordBE(0xf9610060);     // std r11, 96(r1)
+  } else {
+    MCE.emitWordBE(0x9421ffe0);     // stwu r1,-32(r1)
+    MCE.emitWordBE(0x7d6802a6);     // mflr r11
+    MCE.emitWordBE(0x91610028);     // stw r11, 40(r1)
+  }
+  intptr_t Addr = (intptr_t)MCE.getCurrentPCValue();
+  MCE.emitWordBE(0);
+  MCE.emitWordBE(0);
+  MCE.emitWordBE(0);
+  MCE.emitWordBE(0);
+  MCE.emitWordBE(0);
+  MCE.emitWordBE(0);
+  MCE.emitWordBE(0);
+  EmitBranchToAt(Addr, (intptr_t)Fn, true, is64Bit);
+  return MCE.finishFunctionStub(0);
+}
+
+
+void PPCJITInfo::relocate(void *Function, MachineRelocation *MR,
+                          unsigned NumRelocs, unsigned char* GOTBase) {
+  for (unsigned i = 0; i != NumRelocs; ++i, ++MR) {
+    unsigned *RelocPos = (unsigned*)Function + MR->getMachineCodeOffset()/4;
+    intptr_t ResultPtr = (intptr_t)MR->getResultPointer();
+    switch ((PPC::RelocationType)MR->getRelocationType()) {
+    default: assert(0 && "Unknown relocation type!");
+    case PPC::reloc_pcrel_bx:
+      // PC-relative relocation for b and bl instructions.
+      ResultPtr = (ResultPtr-(intptr_t)RelocPos) >> 2;
+      assert(ResultPtr >= -(1 << 23) && ResultPtr < (1 << 23) &&
+             "Relocation out of range!");
+      *RelocPos |= (ResultPtr & ((1 << 24)-1))  << 2;
+      break;
+    case PPC::reloc_pcrel_bcx:
+      // PC-relative relocation for BLT,BLE,BEQ,BGE,BGT,BNE, or other
+      // bcx instructions.
+      ResultPtr = (ResultPtr-(intptr_t)RelocPos) >> 2;
+      assert(ResultPtr >= -(1 << 13) && ResultPtr < (1 << 13) &&
+             "Relocation out of range!");
+      *RelocPos |= (ResultPtr & ((1 << 14)-1))  << 2;
+      break;
+    case PPC::reloc_absolute_high:     // high bits of ref -> low 16 of instr
+    case PPC::reloc_absolute_low: {    // low bits of ref  -> low 16 of instr
+      ResultPtr += MR->getConstantVal();
+
+      // If this is a high-part access, get the high-part.
+      if (MR->getRelocationType() == PPC::reloc_absolute_high) {
+        // If the low part will have a carry (really a borrow) from the low
+        // 16-bits into the high 16, add a bit to borrow from.
+        if (((int)ResultPtr << 16) < 0)
+          ResultPtr += 1 << 16;
+        ResultPtr >>= 16;
+      }
+
+      // Do the addition then mask, so the addition does not overflow the 16-bit
+      // immediate section of the instruction.
+      unsigned LowBits  = (*RelocPos + ResultPtr) & 65535;
+      unsigned HighBits = *RelocPos & ~65535;
+      *RelocPos = LowBits | HighBits;  // Slam into low 16-bits
+      break;
+    }
+    case PPC::reloc_absolute_low_ix: {  // low bits of ref  -> low 14 of instr
+      ResultPtr += MR->getConstantVal();
+      // Do the addition then mask, so the addition does not overflow the 16-bit
+      // immediate section of the instruction.
+      unsigned LowBits  = (*RelocPos + ResultPtr) & 0xFFFC;
+      unsigned HighBits = *RelocPos & 0xFFFF0003;
+      *RelocPos = LowBits | HighBits;  // Slam into low 14-bits.
+      break;
+    }
+    }
+  }
+}
+
+void PPCJITInfo::replaceMachineCodeForFunction(void *Old, void *New) {
+  EmitBranchToAt((intptr_t)Old, (intptr_t)New, false, is64Bit);
+}


Index: llvm/lib/Target/PowerPC/PPCMachOWriter.cpp
diff -u llvm/lib/Target/PowerPC/PPCMachOWriter.cpp:1.3 llvm/lib/Target/PowerPC/PPCMachOWriter.cpp:1.4
--- llvm/lib/Target/PowerPC/PPCMachOWriter.cpp:1.3	Sun Sep  3 23:14:57 2006
+++ llvm/lib/Target/PowerPC/PPCMachOWriter.cpp	Fri Sep  8 17:42:09 2006
@@ -12,6 +12,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "PPCRelocations.h"
 #include "PPCTargetMachine.h"
 #include "llvm/PassManager.h"
 #include "llvm/CodeGen/MachOWriter.h"
@@ -22,11 +23,28 @@
   class VISIBILITY_HIDDEN PPCMachOWriter : public MachOWriter {
   public:
     PPCMachOWriter(std::ostream &O, PPCTargetMachine &TM) : MachOWriter(O, TM) {
-      // FIMXE: choose ppc64 when appropriate
-      Header.cputype = MachOHeader::CPU_TYPE_POWERPC;
+      if (TM.getTargetData()->getPointerSizeInBits() == 64) {
+        Header.cputype = MachOHeader::CPU_TYPE_POWERPC64;
+      } else {
+        Header.cputype = MachOHeader::CPU_TYPE_POWERPC;
+      }
       Header.cpusubtype = MachOHeader::CPU_SUBTYPE_POWERPC_ALL;
     }
 
+    virtual void GetTargetRelocation(MachOSection &MOS, MachineRelocation &MR,
+                                     uint64_t Addr);
+    
+    // Constants for the relocation r_type field.
+    // see <mach-o/ppc/reloc.h>
+    enum { PPC_RELOC_VANILLA, // generic relocation
+           PPC_RELOC_PAIR,    // the second relocation entry of a pair
+           PPC_RELOC_BR14,    // 14 bit branch displacement to word address
+           PPC_RELOC_BR24,    // 24 bit branch displacement to word address
+           PPC_RELOC_HI16,    // a PAIR follows with the low 16 bits
+           PPC_RELOC_LO16,    // a PAIR follows with the high 16 bits
+           PPC_RELOC_HA16,    // a PAIR follows, which is sign extended to 32b
+           PPC_RELOC_LO14     // LO16 with low 2 bits implicitly zero
+    };
   };
 }
 
@@ -39,3 +57,69 @@
   FPM.add(EW);
   FPM.add(createPPCCodeEmitterPass(TM, EW->getMachineCodeEmitter()));
 }
+
+/// GetTargetRelocation - For the MachineRelocation MR, convert it to one or
+/// more PowerPC MachORelocation(s), add the new relocations to the
+/// MachOSection, and rewrite the instruction at the section offset if required 
+/// by that relocation type.
+void PPCMachOWriter::GetTargetRelocation(MachOSection &MOS,
+                                         MachineRelocation &MR,
+                                         uint64_t Addr) {
+  // Keep track of whether or not this is an externally defined relocation.
+  uint32_t index = MOS.Index;
+  bool     isExtern = false;
+  
+  // Get the address of the instruction to rewrite
+  unsigned char *RelocPos = &MOS.SectionData[0] + MR.getMachineCodeOffset();
+  
+  // Get the address of whatever it is we're relocating, if possible.
+  if (MR.isGlobalValue()) {
+    // determine whether or not its external and then figure out what section
+    // we put it in if it's a locally defined symbol.
+  } else if (MR.isString()) {
+    // lookup in global values?
+  } else {
+    assert((MR.isConstantPoolIndex() || MR.isJumpTableIndex()) &&
+           "Unhandled MachineRelocation type!");
+  }
+  
+  switch ((PPC::RelocationType)MR.getRelocationType()) {
+  default: assert(0 && "Unknown PPC relocation type!");
+  case PPC::reloc_pcrel_bx:
+  case PPC::reloc_pcrel_bcx:
+  case PPC::reloc_absolute_low_ix:
+    assert(0 && "Unhandled PPC relocation type!");
+    break;
+  case PPC::reloc_absolute_high:
+    {
+      MachORelocation HA16(MR.getMachineCodeOffset(), index, false, 2, isExtern, 
+                           PPC_RELOC_HA16);
+      MachORelocation PAIR(Addr & 0xFFFF, 0xFFFFFF, false, 2, isExtern,
+                           PPC_RELOC_PAIR);
+      outword(RelocBuffer, HA16.r_address);
+      outword(RelocBuffer, HA16.getPackedFields());
+      outword(RelocBuffer, PAIR.r_address);
+      outword(RelocBuffer, PAIR.getPackedFields());
+    }
+    MOS.nreloc += 2;
+    Addr += 0x8000;
+    *(unsigned *)RelocPos &= 0xFFFF0000;
+    *(unsigned *)RelocPos |= ((Addr >> 16) & 0xFFFF);
+    break;
+  case PPC::reloc_absolute_low:
+    {
+      MachORelocation LO16(MR.getMachineCodeOffset(), index, false, 2, isExtern, 
+                           PPC_RELOC_LO16);
+      MachORelocation PAIR(Addr >> 16, 0xFFFFFF, false, 2, isExtern,
+                           PPC_RELOC_PAIR);
+      outword(RelocBuffer, LO16.r_address);
+      outword(RelocBuffer, LO16.getPackedFields());
+      outword(RelocBuffer, PAIR.r_address);
+      outword(RelocBuffer, PAIR.getPackedFields());
+    }
+    MOS.nreloc += 2;
+    *(unsigned *)RelocPos &= 0xFFFF0000;
+    *(unsigned *)RelocPos |= (Addr & 0xFFFF);
+    break;
+  }
+}


Index: llvm/lib/Target/PowerPC/PPCRelocations.h
diff -u llvm/lib/Target/PowerPC/PPCRelocations.h:1.9 llvm/lib/Target/PowerPC/PPCRelocations.h:1.10
--- llvm/lib/Target/PowerPC/PPCRelocations.h:1.9	Thu Jul 27 13:20:32 2006
+++ llvm/lib/Target/PowerPC/PPCRelocations.h	Fri Sep  8 17:42:09 2006
@@ -44,21 +44,7 @@
       
       // reloc_absolute_low_ix - Absolute relocation for the 64-bit load/store
       // instruction which have two implicit zero bits.
-      reloc_absolute_low_ix,
-
-      // reloc_absolute_ptr_high - Absolute relocation for references to lazy
-      // pointer stubs.  In this case, the relocated instruction should be
-      // relocated to point to a POINTER to the indicated global.  The low-16
-      // bits of the instruction are rewritten with the high 16-bits of the
-      // address of the pointer.
-      reloc_absolute_ptr_high,
-
-      // reloc_absolute_ptr_low - Absolute relocation for references to lazy
-      // pointer stubs.  In this case, the relocated instruction should be
-      // relocated to point to a POINTER to the indicated global.  The low-16
-      // bits of the instruction are rewritten with the low 16-bits of the
-      // address of the pointer.
-      reloc_absolute_ptr_low
+      reloc_absolute_low_ix
     };
   }
 }






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