Implement a basic MCCodeEmitter for PPC. This doesn't handle

fixups yet, and doesn't handle actually encoding operand values,
but this is enough for llc -show-mc-encoding to show the base
instruction encoding information, e.g.:

	mflr r0                         ; encoding: [0x7c,0x08,0x02,0xa6]
	stw r0, 8(r1)                   ; encoding: [0x90,0x00,0x00,0x00]
	stwu r1, -64(r1)                ; encoding: [0x94,0x00,0x00,0x00]
Ltmp0:
	lhz r4, 4(r3)                   ; encoding: [0xa0,0x00,0x00,0x00]
	cmplwi cr0, r4, 8               ; encoding: [0x28,0x00,0x00,0x00]
	beq cr0, LBB0_2                 ; encoding: [0x40,0x00,0x00,0x00]



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119116 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 99 insertions, 0 deletions

diff --git a/lib/Target/PowerPC/PPCMCCodeEmitter.cpp b/lib/Target/PowerPC/PPCMCCodeEmitter.cpp
new file mode 100644
index 0000000000..ecff0e8b2b
--- /dev/null
+++ b/lib/Target/PowerPC/PPCMCCodeEmitter.cpp
@@ -0,0 +1,99 @@
+//===-- PPCMCCodeEmitter.cpp - Convert PPC code to machine code -----------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the PPCMCCodeEmitter class.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "mccodeemitter"
+#include "PPC.h"
+#include "llvm/MC/MCCodeEmitter.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/ErrorHandling.h"
+using namespace llvm;
+
+STATISTIC(MCNumEmitted, "Number of MC instructions emitted");
+
+namespace {
+class PPCMCCodeEmitter : public MCCodeEmitter {
+  PPCMCCodeEmitter(const PPCMCCodeEmitter &); // DO NOT IMPLEMENT
+  void operator=(const PPCMCCodeEmitter &);   // DO NOT IMPLEMENT
+  const TargetMachine &TM;
+  MCContext &Ctx;
+  
+public:
+  PPCMCCodeEmitter(TargetMachine &tm, MCContext &ctx)
+    : TM(tm), Ctx(ctx) {
+  }
+  
+  ~PPCMCCodeEmitter() {}
+  
+  unsigned getNumFixupKinds() const { return 0 /*PPC::NumTargetFixupKinds*/; }
+  
+  const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const {
+    const static MCFixupKindInfo Infos[] = {
+#if 0
+      // name                     offset  bits  flags
+      { "fixup_arm_pcrel_12",     2,      12,   MCFixupKindInfo::FKF_IsPCRel },
+      { "fixup_arm_vfp_pcrel_12", 3,      8,    MCFixupKindInfo::FKF_IsPCRel },
+      { "fixup_arm_branch",       1,      24,   MCFixupKindInfo::FKF_IsPCRel },
+#endif
+    };
+    
+    if (Kind < FirstTargetFixupKind)
+      return MCCodeEmitter::getFixupKindInfo(Kind);
+    
+    assert(unsigned(Kind - FirstTargetFixupKind) < getNumFixupKinds() &&
+           "Invalid kind!");
+    return Infos[Kind - FirstTargetFixupKind];
+  }
+  
+  /// getMachineOpValue - Return binary encoding of operand. If the machine
+  /// operand requires relocation, record the relocation and return zero.
+  unsigned getMachineOpValue(const MCInst &MI,const MCOperand &MO,
+                             SmallVectorImpl<MCFixup> &Fixups) const;
+    
+  
+  // getBinaryCodeForInstr - TableGen'erated function for getting the
+  // binary encoding for an instruction.
+  unsigned getBinaryCodeForInstr(const MCInst &MI,
+                                 SmallVectorImpl<MCFixup> &Fixups) const;
+  void EncodeInstruction(const MCInst &MI, raw_ostream &OS,
+                         SmallVectorImpl<MCFixup> &Fixups) const {
+    unsigned Bits = getBinaryCodeForInstr(MI, Fixups);
+    
+    // Output the constant in big endian byte order.
+    for (unsigned i = 0; i != 4; ++i) {
+      OS << (char)(Bits >> 24);
+      Bits <<= 8;
+    }
+    
+    ++MCNumEmitted;  // Keep track of the # of mi's emitted.
+  }
+  
+};
+  
+} // end anonymous namespace
+  
+MCCodeEmitter *llvm::createPPCMCCodeEmitter(const Target &, TargetMachine &TM,
+                                            MCContext &Ctx) {
+  return new PPCMCCodeEmitter(TM, Ctx);
+}
+
+unsigned PPCMCCodeEmitter::
+getMachineOpValue(const MCInst &MI, const MCOperand &MO,
+                  SmallVectorImpl<MCFixup> &Fixups) const {
+  // FIXME.
+  return 0;
+}
+
+
+#include "PPCGenMCCodeEmitter.inc"