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diff --git a/include/llvm/CodeGen/MachineRelocation.h b/include/llvm/CodeGen/MachineRelocation.h
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+//===-- llvm/CodeGen/MachineRelocation.h - Target Relocation ----*- C++ -*-===//
+//
+// 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 defines the MachineRelocation class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_MACHINERELOCATION_H
+#define LLVM_CODEGEN_MACHINERELOCATION_H
+
+#include "llvm/Support/DataTypes.h"
+#include <cassert>
+
+namespace llvm {
+class GlobalValue;
+
+/// MachineRelocation - This represents a target-specific relocation value,
+/// produced by the code emitter. This relocation is resolved after the has
+/// been emitted, either to an object file or to memory, when the target of the
+/// relocation can be resolved.
+///
+/// A relocation is made up of the following logical portions:
+/// 1. An offset in the machine code buffer, the location to modify.
+/// 2. A target specific relocation type (a number from 0 to 63).
+/// 3. A symbol being referenced, either as a GlobalValue* or as a string.
+/// 4. An optional constant value to be added to the reference.
+/// 5. A bit, CanRewrite, which indicates to the JIT that a function stub is
+/// not needed for the relocation.
+/// 6. An index into the GOT, if the target uses a GOT
+///
+class MachineRelocation {
+ /// OffsetTypeExternal - The low 24-bits of this value is the offset from the
+ /// start of the code buffer of the relocation to perform. Bit 24 of this is
+ /// set if Target should use ExtSym instead of GV, Bit 25 is the CanRewrite
+ /// bit, and the high 6 bits hold the relocation type.
+ // FIXME: with the additional types of relocatable things, rearrange the
+ // storage of things to be a bit more effiecient
+ unsigned OffsetTypeExternal;
+ union {
+ GlobalValue *GV; // If this is a pointer to an LLVM global
+ const char *ExtSym; // If this is a pointer to a named symbol
+ void *Result; // If this has been resolved to a resolved pointer
+ unsigned GOTIndex; // Index in the GOT of this symbol/global
+ unsigned CPool; // Index in the Constant Pool
+ } Target;
+ intptr_t ConstantVal;
+ bool GOTRelative; //out of bits in OffsetTypeExternal
+ bool isConstPool;
+
+public:
+ MachineRelocation(unsigned Offset, unsigned RelocationType, GlobalValue *GV,
+ intptr_t cst = 0, bool DoesntNeedFunctionStub = 0,
+ bool GOTrelative = 0)
+ : OffsetTypeExternal(Offset + (RelocationType << 26)), ConstantVal(cst),
+ GOTRelative(GOTrelative), isConstPool(0) {
+ assert((Offset & ~((1 << 24)-1)) == 0 && "Code offset too large!");
+ assert((RelocationType & ~63) == 0 && "Relocation type too large!");
+ Target.GV = GV;
+ if (DoesntNeedFunctionStub)
+ OffsetTypeExternal |= 1 << 25;
+ }
+
+ MachineRelocation(unsigned Offset, unsigned RelocationType, const char *ES,
+ intptr_t cst = 0, bool GOTrelative = 0)
+ : OffsetTypeExternal(Offset + (1 << 24) + (RelocationType << 26)),
+ ConstantVal(cst), GOTRelative(GOTrelative), isConstPool(0) {
+ assert((Offset & ~((1 << 24)-1)) == 0 && "Code offset too large!");
+ assert((RelocationType & ~63) == 0 && "Relocation type too large!");
+ Target.ExtSym = ES;
+ }
+
+ MachineRelocation(unsigned Offset, unsigned RelocationType, unsigned CPI,
+ intptr_t cst = 0)
+ : OffsetTypeExternal(Offset + (RelocationType << 26)),
+ ConstantVal(cst), GOTRelative(0), isConstPool(1) {
+ assert((Offset & ~((1 << 24)-1)) == 0 && "Code offset too large!");
+ assert((RelocationType & ~63) == 0 && "Relocation type too large!");
+ Target.CPool = CPI;
+ }
+
+ /// getMachineCodeOffset - Return the offset into the code buffer that the
+ /// relocation should be performed.
+ unsigned getMachineCodeOffset() const {
+ return OffsetTypeExternal & ((1 << 24)-1);
+ }
+
+ /// getRelocationType - Return the target-specific relocation ID for this
+ /// relocation.
+ unsigned getRelocationType() const {
+ return OffsetTypeExternal >> 26;
+ }
+
+ /// getConstantVal - Get the constant value associated with this relocation.
+ /// This is often an offset from the symbol.
+ ///
+ intptr_t getConstantVal() const {
+ return ConstantVal;
+ }
+
+ /// isGlobalValue - Return true if this relocation is a GlobalValue, as
+ /// opposed to a constant string.
+ bool isGlobalValue() const {
+ return (OffsetTypeExternal & (1 << 24)) == 0 && !isConstantPoolIndex();
+ }
+
+ /// isString - Return true if this is a constant string.
+ ///
+ bool isString() const {
+ return !isGlobalValue() && !isConstantPoolIndex();
+ }
+
+ /// isConstantPoolIndex - Return true if this is a constant pool reference.
+ ///
+ bool isConstantPoolIndex() const {
+ return isConstPool;
+ }
+
+ /// isGOTRelative - Return true the target wants the index into the GOT of
+ /// the symbol rather than the address of the symbol.
+ bool isGOTRelative() const {
+ return GOTRelative;
+ }
+
+ /// doesntNeedFunctionStub - This function returns true if the JIT for this
+ /// target is capable of directly handling the relocated instruction without
+ /// using a stub function. It is always conservatively correct for this flag
+ /// to be false, but targets can improve their compilation callback functions
+ /// to handle more general cases if they want improved performance.
+ bool doesntNeedFunctionStub() const {
+ return (OffsetTypeExternal & (1 << 25)) != 0;
+ }
+
+ /// getGlobalValue - If this is a global value reference, return the
+ /// referenced global.
+ GlobalValue *getGlobalValue() const {
+ assert(isGlobalValue() && "This is not a global value reference!");
+ return Target.GV;
+ }
+
+ /// getString - If this is a string value, return the string reference.
+ ///
+ const char *getString() const {
+ assert(isString() && "This is not a string reference!");
+ return Target.ExtSym;
+ }
+
+ /// getConstantPoolIndex - If this is a const pool reference, return
+ /// the index into the constant pool.
+ unsigned getConstantPoolIndex() const {
+ assert(isConstantPoolIndex() && "This is not a constant pool reference!");
+ return Target.CPool;
+ }
+
+ /// getResultPointer - Once this has been resolved to point to an actual
+ /// address, this returns the pointer.
+ void *getResultPointer() const {
+ return Target.Result;
+ }
+
+ /// setResultPointer - Set the result to the specified pointer value.
+ ///
+ void setResultPointer(void *Ptr) {
+ Target.Result = Ptr;
+ }
+
+ /// setGOTIndex - Set the GOT index to a specific value.
+ void setGOTIndex(unsigned idx) {
+ Target.GOTIndex = idx;
+ }
+
+ /// getGOTIndex - Once this has been resolved to an entry in the GOT,
+ /// this returns that index. The index is from the lowest address entry
+ /// in the GOT.
+ unsigned getGOTIndex() const {
+ return Target.GOTIndex;
+ }
+
+};
+
+}
+
+#endif