Fix a purely hypothetical problem (for now): emitWord emits in the host

byte format.  This doesn't work when using the code emitter in a cross target
environment.  Since the code emitter is only really used by the JIT, this
isn't a current problem, but if we ever start emitting .o files, it would be.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28060 91177308-0d34-0410-b5e6-96231b3b80d8

7 files changed, 42 insertions, 35 deletions

diff --git a/include/llvm/CodeGen/MachineCodeEmitter.h b/include/llvm/CodeGen/MachineCodeEmitter.h
index 72002ef..7f171b6 100644
--- a/include/llvm/CodeGen/MachineCodeEmitter.h
+++ b/include/llvm/CodeGen/MachineCodeEmitter.h
@@ -112,14 +112,29 @@ public:
       *CurBufferPtr++ = B;
   }
 
-  /// emitWord - This callback is invoked when a word needs to be written to the
-  /// output stream.
+  /// emitWordLE - This callback is invoked when a 32-bit word needs to be
+  /// written to the output stream in little-endian format.
+  ///
+  void emitWordLE(unsigned W) {
+    if (CurBufferPtr+4 <= BufferEnd) {
+      *CurBufferPtr++ = (unsigned char)(W >>  0);
+      *CurBufferPtr++ = (unsigned char)(W >>  8);
+      *CurBufferPtr++ = (unsigned char)(W >> 16);
+      *CurBufferPtr++ = (unsigned char)(W >> 24);
+    } else {
+      CurBufferPtr = BufferEnd;
+    }
+  }
+  
+  /// emitWordBE - This callback is invoked when a 32-bit word needs to be
+  /// written to the output stream in big-endian format.
   ///
-  void emitWord(unsigned W) {
-    // FIXME: handle endian mismatches for .o file emission.
+  void emitWordBE(unsigned W) {
     if (CurBufferPtr+4 <= BufferEnd) {
-      *(unsigned*)CurBufferPtr = W;
-      CurBufferPtr += 4;
+      *CurBufferPtr++ = (unsigned char)(W >> 24);
+      *CurBufferPtr++ = (unsigned char)(W >> 16);
+      *CurBufferPtr++ = (unsigned char)(W >>  8);
+      *CurBufferPtr++ = (unsigned char)(W >>  0);
     } else {
       CurBufferPtr = BufferEnd;
     }
diff --git a/lib/Target/Alpha/AlphaCodeEmitter.cpp b/lib/Target/Alpha/AlphaCodeEmitter.cpp
index dfb7820..a04cd37 100644
--- a/lib/Target/Alpha/AlphaCodeEmitter.cpp
+++ b/lib/Target/Alpha/AlphaCodeEmitter.cpp
@@ -55,10 +55,6 @@ namespace {
 
     void emitInstruction(const MachineInstr &MI);
 
-    /// emitWord - write a 32-bit word to memory at the current PC
-    ///
-    void emitWord(unsigned w) { MCE.emitWord(w); }
-
     /// getBinaryCodeForInstr - This function, generated by the
     /// CodeEmitterGenerator using TableGen, produces the binary encoding for
     /// machine instructions.
@@ -117,7 +113,7 @@ void AlphaCodeEmitter::emitBasicBlock(MachineBasicBlock &MBB) {
     unsigned Opcode = MI.getOpcode();
     switch(MI.getOpcode()) {
     default:
-      emitWord(getBinaryCodeForInstr(*I));
+      MCE.emitWordLE(getBinaryCodeForInstr(*I));
       break;
     case Alpha::ALTENT:
     case Alpha::PCLABEL:
diff --git a/lib/Target/Alpha/AlphaJITInfo.cpp b/lib/Target/Alpha/AlphaJITInfo.cpp
index 6d20ec3..81f5e74 100644
--- a/lib/Target/Alpha/AlphaJITInfo.cpp
+++ b/lib/Target/Alpha/AlphaJITInfo.cpp
@@ -197,7 +197,7 @@ void *AlphaJITInfo::emitFunctionStub(void *Fn, MachineCodeEmitter &MCE) {
   MCE.startFunctionStub(19*4);
   void* Addr = (void*)(intptr_t)MCE.getCurrentPCValue();
   for (int x = 0; x < 19; ++ x)
-    MCE.emitWord(0);
+    MCE.emitWordLE(0);
   EmitBranchToAt(Addr, Fn);
   DEBUG(std::cerr << "Emitting Stub to " << Fn << " at [" << Addr << "]\n");
   return MCE.finishFunctionStub(0);
diff --git a/lib/Target/PowerPC/PPCCodeEmitter.cpp b/lib/Target/PowerPC/PPCCodeEmitter.cpp
index 1b305f4..6fe6829 100644
--- a/lib/Target/PowerPC/PPCCodeEmitter.cpp
+++ b/lib/Target/PowerPC/PPCCodeEmitter.cpp
@@ -54,10 +54,6 @@ namespace {
     ///
     void emitBasicBlock(MachineBasicBlock &MBB);
 
-    /// emitWord - write a 32-bit word to memory at the current PC
-    ///
-    void emitWord(unsigned w) { MCE.emitWord(w); }
-
     /// getValueBit - return the particular bit of Val
     ///
     unsigned getValueBit(int64_t Val, unsigned bit) { return (Val >> bit) & 1; }
@@ -133,7 +129,7 @@ void PPCCodeEmitter::emitBasicBlock(MachineBasicBlock &MBB) {
     unsigned Opcode = MI.getOpcode();
     switch (MI.getOpcode()) {
     default:
-      emitWord(getBinaryCodeForInstr(*I));
+      MCE.emitWordBE(getBinaryCodeForInstr(*I));
       break;
     case PPC::IMPLICIT_DEF_GPR:
     case PPC::IMPLICIT_DEF_F8:
diff --git a/lib/Target/PowerPC/PPCJITInfo.cpp b/lib/Target/PowerPC/PPCJITInfo.cpp
index 9329b38..a6d630e 100644
--- a/lib/Target/PowerPC/PPCJITInfo.cpp
+++ b/lib/Target/PowerPC/PPCJITInfo.cpp
@@ -168,23 +168,23 @@ void *PPCJITInfo::emitFunctionStub(void *Fn, MachineCodeEmitter &MCE) {
   if (Fn != PPC32CompilationCallback) {
     MCE.startFunctionStub(4*4);
     void *Addr = (void*)(intptr_t)MCE.getCurrentPCValue();
-    MCE.emitWord(0);
-    MCE.emitWord(0);
-    MCE.emitWord(0);
-    MCE.emitWord(0);
+    MCE.emitWordBE(0);
+    MCE.emitWordBE(0);
+    MCE.emitWordBE(0);
+    MCE.emitWordBE(0);
     EmitBranchToAt(Addr, Fn, false);
     return MCE.finishFunctionStub(0);
   }
 
   MCE.startFunctionStub(4*7);
-  MCE.emitWord(0x9421ffe0);     // stwu    r1,-32(r1)
-  MCE.emitWord(0x7d6802a6);     // mflr r11
-  MCE.emitWord(0x91610028);     // stw r11, 40(r1)
+  MCE.emitWordBE(0x9421ffe0);     // stwu    r1,-32(r1)
+  MCE.emitWordBE(0x7d6802a6);     // mflr r11
+  MCE.emitWordBE(0x91610028);     // stw r11, 40(r1)
   void *Addr = (void*)(intptr_t)MCE.getCurrentPCValue();
-  MCE.emitWord(0);
-  MCE.emitWord(0);
-  MCE.emitWord(0);
-  MCE.emitWord(0);
+  MCE.emitWordBE(0);
+  MCE.emitWordBE(0);
+  MCE.emitWordBE(0);
+  MCE.emitWordBE(0);
   EmitBranchToAt(Addr, Fn, true/*is call*/);
   return MCE.finishFunctionStub(0);
 }
diff --git a/lib/Target/X86/X86CodeEmitter.cpp b/lib/Target/X86/X86CodeEmitter.cpp
index a278fd5..175dae5 100644
--- a/lib/Target/X86/X86CodeEmitter.cpp
+++ b/lib/Target/X86/X86CodeEmitter.cpp
@@ -116,7 +116,7 @@ void Emitter::emitBasicBlock(MachineBasicBlock &MBB) {
 /// emitPCRelativeValue - Emit a 32-bit PC relative address.
 ///
 void Emitter::emitPCRelativeValue(unsigned Address) {
-  MCE.emitWord(Address-MCE.getCurrentPCValue()-4);
+  MCE.emitWordLE(Address-MCE.getCurrentPCValue()-4);
 }
 
 /// emitPCRelativeBlockAddress - This method emits the PC relative address of
@@ -134,7 +134,7 @@ void Emitter::emitPCRelativeBlockAddress(MachineBasicBlock *MBB) {
     // Otherwise, remember where this reference was and where it is to so we can
     // deal with it later.
     BBRefs.push_back(std::make_pair(MBB, MCE.getCurrentPCValue()));
-    MCE.emitWord(0);
+    MCE.emitWordLE(0);
   }
 }
 
@@ -145,7 +145,7 @@ void Emitter::emitGlobalAddressForCall(GlobalValue *GV, bool isTailCall) {
   MCE.addRelocation(MachineRelocation(MCE.getCurrentPCOffset(),
                                       X86::reloc_pcrel_word, GV, 0,
                                       !isTailCall /*Doesn'tNeedStub*/));
-  MCE.emitWord(0);
+  MCE.emitWordLE(0);
 }
 
 /// emitGlobalAddress - Emit the specified address to the code stream assuming
@@ -155,7 +155,7 @@ void Emitter::emitGlobalAddressForCall(GlobalValue *GV, bool isTailCall) {
 void Emitter::emitGlobalAddressForPtr(GlobalValue *GV, int Disp /* = 0 */) {
   MCE.addRelocation(MachineRelocation(MCE.getCurrentPCOffset(),
                                       X86::reloc_absolute_word, GV));
-  MCE.emitWord(Disp);   // The relocated value will be added to the displacement
+  MCE.emitWordLE(Disp); // The relocated value will be added to the displacement
 }
 
 /// emitExternalSymbolAddress - Arrange for the address of an external symbol to
@@ -165,7 +165,7 @@ void Emitter::emitExternalSymbolAddress(const char *ES, bool isPCRelative,
                                         bool isTailCall) {
   MCE.addRelocation(MachineRelocation(MCE.getCurrentPCOffset(),
           isPCRelative ? X86::reloc_pcrel_word : X86::reloc_absolute_word, ES));
-  MCE.emitWord(0);
+  MCE.emitWordLE(0);
 }
 
 /// N86 namespace - Native X86 Register numbers... used by X86 backend.
diff --git a/lib/Target/X86/X86JITInfo.cpp b/lib/Target/X86/X86JITInfo.cpp
index 7f93895..3d12221 100644
--- a/lib/Target/X86/X86JITInfo.cpp
+++ b/lib/Target/X86/X86JITInfo.cpp
@@ -170,14 +170,14 @@ void *X86JITInfo::emitFunctionStub(void *Fn, MachineCodeEmitter &MCE) {
   if (Fn != X86CompilationCallback) {
     MCE.startFunctionStub(5);
     MCE.emitByte(0xE9);
-    MCE.emitWord((intptr_t)Fn-MCE.getCurrentPCValue()-4);
+    MCE.emitWordLE((intptr_t)Fn-MCE.getCurrentPCValue()-4);
     return MCE.finishFunctionStub(0);
   }
 
   MCE.startFunctionStub(6);
   MCE.emitByte(0xE8);   // Call with 32 bit pc-rel destination...
 
-  MCE.emitWord((intptr_t)Fn-MCE.getCurrentPCValue()-4);
+  MCE.emitWordLE((intptr_t)Fn-MCE.getCurrentPCValue()-4);
 
   MCE.emitByte(0xCD);   // Interrupt - Just a marker identifying the stub!
   return MCE.finishFunctionStub(0);