llvm-6502/include/llvm/CodeGen/AsmPrinter.h
Evan Cheng cc41586b9d Much improved pic jumptable codegen:
Then:
        call    "L1$pb"
"L1$pb":
        popl    %eax
		...
LBB1_1: # entry
        imull   $4, %ecx, %ecx
        leal    LJTI1_0-"L1$pb"(%eax), %edx
        addl    LJTI1_0-"L1$pb"(%ecx,%eax), %edx
        jmpl    *%edx

        .align  2
        .set L1_0_set_3,LBB1_3-LJTI1_0
        .set L1_0_set_2,LBB1_2-LJTI1_0
        .set L1_0_set_5,LBB1_5-LJTI1_0
        .set L1_0_set_4,LBB1_4-LJTI1_0
LJTI1_0:
        .long    L1_0_set_3
        .long    L1_0_set_2

Now:
        call    "L1$pb"
"L1$pb":
        popl    %eax
		...
LBB1_1: # entry
        addl    LJTI1_0-"L1$pb"(%eax,%ecx,4), %eax
        jmpl    *%eax

		.align  2
		.set L1_0_set_3,LBB1_3-"L1$pb"
		.set L1_0_set_2,LBB1_2-"L1$pb"
		.set L1_0_set_5,LBB1_5-"L1$pb"
		.set L1_0_set_4,LBB1_4-"L1$pb"
LJTI1_0:
        .long    L1_0_set_3
        .long    L1_0_set_2


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43924 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-09 01:32:10 +00:00

329 lines
13 KiB
C++

//===-- llvm/CodeGen/AsmPrinter.h - AsmPrinter Framework --------*- 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 contains a class to be used as the base class for target specific
// asm writers. This class primarily handles common functionality used by
// all asm writers.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_ASMPRINTER_H
#define LLVM_CODEGEN_ASMPRINTER_H
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/Support/DataTypes.h"
#include <set>
namespace llvm {
class Constant;
class ConstantArray;
class GlobalVariable;
class GlobalAlias;
class MachineConstantPoolEntry;
class MachineConstantPoolValue;
class Mangler;
class TargetAsmInfo;
/// AsmPrinter - This class is intended to be used as a driving class for all
/// asm writers.
class AsmPrinter : public MachineFunctionPass {
static char ID;
/// FunctionNumber - This provides a unique ID for each function emitted in
/// this translation unit. It is autoincremented by SetupMachineFunction,
/// and can be accessed with getFunctionNumber() and
/// IncrementFunctionNumber().
///
unsigned FunctionNumber;
protected:
// Necessary for external weak linkage support
std::set<const GlobalValue*> ExtWeakSymbols;
public:
/// Output stream on which we're printing assembly code.
///
std::ostream &O;
/// Target machine description.
///
TargetMachine &TM;
/// Target Asm Printer information.
///
const TargetAsmInfo *TAI;
/// Name-mangler for global names.
///
Mangler *Mang;
/// Cache of mangled name for current function. This is recalculated at the
/// beginning of each call to runOnMachineFunction().
///
std::string CurrentFnName;
/// CurrentSection - The current section we are emitting to. This is
/// controlled and used by the SwitchSection method.
std::string CurrentSection;
protected:
AsmPrinter(std::ostream &o, TargetMachine &TM, const TargetAsmInfo *T);
public:
/// SwitchToTextSection - Switch to the specified section of the executable
/// if we are not already in it! If GV is non-null and if the global has an
/// explicitly requested section, we switch to the section indicated for the
/// global instead of NewSection.
///
/// If the new section is an empty string, this method forgets what the
/// current section is, but does not emit a .section directive.
///
/// This method is used when about to emit executable code.
///
void SwitchToTextSection(const char *NewSection, const GlobalValue *GV = NULL);
/// SwitchToDataSection - Switch to the specified section of the executable
/// if we are not already in it! If GV is non-null and if the global has an
/// explicitly requested section, we switch to the section indicated for the
/// global instead of NewSection.
///
/// If the new section is an empty string, this method forgets what the
/// current section is, but does not emit a .section directive.
///
/// This method is used when about to emit data. For most assemblers, this
/// is the same as the SwitchToTextSection method, but not all assemblers
/// are the same.
///
void SwitchToDataSection(const char *NewSection, const GlobalValue *GV = NULL);
/// getGlobalLinkName - Returns the asm/link name of of the specified
/// global variable. Should be overridden by each target asm printer to
/// generate the appropriate value.
virtual const std::string getGlobalLinkName(const GlobalVariable *GV) const;
/// EmitExternalGlobal - Emit the external reference to a global variable.
/// Should be overridden if an indirect reference should be used.
virtual void EmitExternalGlobal(const GlobalVariable *GV);
/// getCurrentFunctionEHName - Called to return (and cache) the
/// CurrentFnEHName.
///
std::string getCurrentFunctionEHName(const MachineFunction *MF);
protected:
/// doInitialization - Set up the AsmPrinter when we are working on a new
/// module. If your pass overrides this, it must make sure to explicitly
/// call this implementation.
bool doInitialization(Module &M);
/// doFinalization - Shut down the asmprinter. If you override this in your
/// pass, you must make sure to call it explicitly.
bool doFinalization(Module &M);
/// PrintSpecial - Print information related to the specified machine instr
/// that is independent of the operand, and may be independent of the instr
/// itself. This can be useful for portably encoding the comment character
/// or other bits of target-specific knowledge into the asmstrings. The
/// syntax used is ${:comment}. Targets can override this to add support
/// for their own strange codes.
virtual void PrintSpecial(const MachineInstr *MI, const char *Code);
/// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
/// instruction, using the specified assembler variant. Targets should
/// override this to format as appropriate. This method can return true if
/// the operand is erroneous.
virtual bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
unsigned AsmVariant, const char *ExtraCode);
/// PrintAsmMemoryOperand - Print the specified operand of MI, an INLINEASM
/// instruction, using the specified assembler variant as an address.
/// Targets should override this to format as appropriate. This method can
/// return true if the operand is erroneous.
virtual bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
unsigned AsmVariant,
const char *ExtraCode);
/// getSectionForFunction - Return the section that we should emit the
/// specified function body into. This defaults to 'TextSection'. This
/// should most likely be overridden by the target to put linkonce/weak
/// functions into special sections.
virtual std::string getSectionForFunction(const Function &F) const;
/// SetupMachineFunction - This should be called when a new MachineFunction
/// is being processed from runOnMachineFunction.
void SetupMachineFunction(MachineFunction &MF);
/// getFunctionNumber - Return a unique ID for the current function.
///
unsigned getFunctionNumber() const { return FunctionNumber; }
/// IncrementFunctionNumber - Increase Function Number. AsmPrinters should
/// not normally call this, as the counter is automatically bumped by
/// SetupMachineFunction.
void IncrementFunctionNumber() { FunctionNumber++; }
/// EmitConstantPool - Print to the current output stream assembly
/// representations of the constants in the constant pool MCP. This is
/// used to print out constants which have been "spilled to memory" by
/// the code generator.
///
void EmitConstantPool(MachineConstantPool *MCP);
/// EmitJumpTableInfo - Print assembly representations of the jump tables
/// used by the current function to the current output stream.
///
void EmitJumpTableInfo(MachineJumpTableInfo *MJTI, MachineFunction &MF);
/// EmitSpecialLLVMGlobal - Check to see if the specified global is a
/// special global used by LLVM. If so, emit it and return true, otherwise
/// do nothing and return false.
bool EmitSpecialLLVMGlobal(const GlobalVariable *GV);
public:
//===------------------------------------------------------------------===//
/// LEB 128 number encoding.
/// PrintULEB128 - Print a series of hexidecimal values(separated by commas)
/// representing an unsigned leb128 value.
void PrintULEB128(unsigned Value) const;
/// SizeULEB128 - Compute the number of bytes required for an unsigned
/// leb128 value.
static unsigned SizeULEB128(unsigned Value);
/// PrintSLEB128 - Print a series of hexidecimal values(separated by commas)
/// representing a signed leb128 value.
void PrintSLEB128(int Value) const;
/// SizeSLEB128 - Compute the number of bytes required for a signed leb128
/// value.
static unsigned SizeSLEB128(int Value);
//===------------------------------------------------------------------===//
// Emission and print routines
//
/// PrintHex - Print a value as a hexidecimal value.
///
void PrintHex(int Value) const;
/// EOL - Print a newline character to asm stream. If a comment is present
/// then it will be printed first. Comments should not contain '\n'.
void EOL() const;
void EOL(const std::string &Comment) const;
/// EmitULEB128Bytes - Emit an assembler byte data directive to compose an
/// unsigned leb128 value.
void EmitULEB128Bytes(unsigned Value) const;
/// EmitSLEB128Bytes - print an assembler byte data directive to compose a
/// signed leb128 value.
void EmitSLEB128Bytes(int Value) const;
/// EmitInt8 - Emit a byte directive and value.
///
void EmitInt8(int Value) const;
/// EmitInt16 - Emit a short directive and value.
///
void EmitInt16(int Value) const;
/// EmitInt32 - Emit a long directive and value.
///
void EmitInt32(int Value) const;
/// EmitInt64 - Emit a long long directive and value.
///
void EmitInt64(uint64_t Value) const;
/// EmitString - Emit a string with quotes and a null terminator.
/// Special characters are emitted properly.
/// @verbatim (Eg. '\t') @endverbatim
void EmitString(const std::string &String) const;
/// EmitFile - Emit a .file directive.
void EmitFile(unsigned Number, const std::string &Name) const;
//===------------------------------------------------------------------===//
/// EmitAlignment - Emit an alignment directive to the specified power of
/// two boundary. For example, if you pass in 3 here, you will get an 8
/// byte alignment. If a global value is specified, and if that global has
/// an explicit alignment requested, it will unconditionally override the
/// alignment request. However, if ForcedAlignBits is specified, this value
/// has final say: the ultimate alignment will be the max of ForcedAlignBits
/// and the alignment computed with NumBits and the global. If UseFillExpr
/// is true, it also emits an optional second value FillValue which the
/// assembler uses to fill gaps to match alignment.
///
/// The algorithm is:
/// Align = NumBits;
/// if (GV && GV->hasalignment) Align = GV->getalignment();
/// Align = std::max(Align, ForcedAlignBits);
///
void EmitAlignment(unsigned NumBits, const GlobalValue *GV = 0,
unsigned ForcedAlignBits = 0, bool UseFillExpr = false,
unsigned FillValue = 0) const;
protected:
/// EmitZeros - Emit a block of zeros.
///
void EmitZeros(uint64_t NumZeros) const;
/// EmitString - Emit a zero-byte-terminated string constant.
///
virtual void EmitString(const ConstantArray *CVA) const;
/// EmitConstantValueOnly - Print out the specified constant, without a
/// storage class. Only constants of first-class type are allowed here.
void EmitConstantValueOnly(const Constant *CV);
/// EmitGlobalConstant - Print a general LLVM constant to the .s file.
/// If Packed is false, pad to the ABI size.
void EmitGlobalConstant(const Constant* CV, bool Packed = false);
virtual void EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV);
/// printInlineAsm - This method formats and prints the specified machine
/// instruction that is an inline asm.
void printInlineAsm(const MachineInstr *MI) const;
/// printLabel - This method prints a local label used by debug and
/// exception handling tables.
void printLabel(const MachineInstr *MI) const;
/// printBasicBlockLabel - This method prints the label for the specified
/// MachineBasicBlock
virtual void printBasicBlockLabel(const MachineBasicBlock *MBB,
bool printColon = false,
bool printComment = true) const;
/// printPICJumpTableSetLabel - This method prints a set label for the
/// specified MachineBasicBlock for a jumptable entry.
virtual void printPICJumpTableSetLabel(unsigned uid,
const MachineBasicBlock *MBB) const;
virtual void printPICJumpTableSetLabel(unsigned uid, unsigned uid2,
const MachineBasicBlock *MBB) const;
/// printDataDirective - This method prints the asm directive for the
/// specified type.
void printDataDirective(const Type *type);
private:
void EmitLLVMUsedList(Constant *List);
void EmitXXStructorList(Constant *List);
void EmitConstantPool(unsigned Alignment, const char *Section,
std::vector<std::pair<MachineConstantPoolEntry,unsigned> > &CP);
};
}
#endif