llvm-6502/include/llvm/Target/TargetOpcodes.h
Rafael Espindola 7d7d99622f Replace PROLOG_LABEL with a new CFI_INSTRUCTION.
The old system was fairly convoluted:
* A temporary label was created.
* A single PROLOG_LABEL was created with it.
* A few MCCFIInstructions were created with the same label.

The semantics were that the cfi instructions were mapped to the PROLOG_LABEL
via the temporary label. The output position was that of the PROLOG_LABEL.
The temporary label itself was used only for doing the mapping.

The new CFI_INSTRUCTION has a 1:1 mapping to MCCFIInstructions and points to
one by holding an index into the CFI instructions of this function.

I did consider removing MMI.getFrameInstructions completelly and having
CFI_INSTRUCTION own a MCCFIInstruction, but MCCFIInstructions have non
trivial constructors and destructors and are somewhat big, so the this setup
is probably better.

The net result is that we don't create temporary labels that are never used.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203204 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-07 06:08:31 +00:00

113 lines
4.5 KiB
C++

//===-- llvm/Target/TargetOpcodes.h - Target Indep Opcodes ------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the target independent instruction opcodes.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TARGET_TARGETOPCODES_H
#define LLVM_TARGET_TARGETOPCODES_H
namespace llvm {
/// Invariant opcodes: All instruction sets have these as their low opcodes.
///
/// Every instruction defined here must also appear in Target.td and the order
/// must be the same as in CodeGenTarget.cpp.
///
namespace TargetOpcode {
enum {
PHI = 0,
INLINEASM = 1,
CFI_INSTRUCTION = 2,
EH_LABEL = 3,
GC_LABEL = 4,
/// KILL - This instruction is a noop that is used only to adjust the
/// liveness of registers. This can be useful when dealing with
/// sub-registers.
KILL = 5,
/// EXTRACT_SUBREG - This instruction takes two operands: a register
/// that has subregisters, and a subregister index. It returns the
/// extracted subregister value. This is commonly used to implement
/// truncation operations on target architectures which support it.
EXTRACT_SUBREG = 6,
/// INSERT_SUBREG - This instruction takes three operands: a register that
/// has subregisters, a register providing an insert value, and a
/// subregister index. It returns the value of the first register with the
/// value of the second register inserted. The first register is often
/// defined by an IMPLICIT_DEF, because it is commonly used to implement
/// anyext operations on target architectures which support it.
INSERT_SUBREG = 7,
/// IMPLICIT_DEF - This is the MachineInstr-level equivalent of undef.
IMPLICIT_DEF = 8,
/// SUBREG_TO_REG - This instruction is similar to INSERT_SUBREG except that
/// the first operand is an immediate integer constant. This constant is
/// often zero, because it is commonly used to assert that the instruction
/// defining the register implicitly clears the high bits.
SUBREG_TO_REG = 9,
/// COPY_TO_REGCLASS - This instruction is a placeholder for a plain
/// register-to-register copy into a specific register class. This is only
/// used between instruction selection and MachineInstr creation, before
/// virtual registers have been created for all the instructions, and it's
/// only needed in cases where the register classes implied by the
/// instructions are insufficient. It is emitted as a COPY MachineInstr.
COPY_TO_REGCLASS = 10,
/// DBG_VALUE - a mapping of the llvm.dbg.value intrinsic
DBG_VALUE = 11,
/// REG_SEQUENCE - This variadic instruction is used to form a register that
/// represents a consecutive sequence of sub-registers. It's used as a
/// register coalescing / allocation aid and must be eliminated before code
/// emission.
// In SDNode form, the first operand encodes the register class created by
// the REG_SEQUENCE, while each subsequent pair names a vreg + subreg index
// pair. Once it has been lowered to a MachineInstr, the regclass operand
// is no longer present.
/// e.g. v1027 = REG_SEQUENCE v1024, 3, v1025, 4, v1026, 5
/// After register coalescing references of v1024 should be replace with
/// v1027:3, v1025 with v1027:4, etc.
REG_SEQUENCE = 12,
/// COPY - Target-independent register copy. This instruction can also be
/// used to copy between subregisters of virtual registers.
COPY = 13,
/// BUNDLE - This instruction represents an instruction bundle. Instructions
/// which immediately follow a BUNDLE instruction which are marked with
/// 'InsideBundle' flag are inside the bundle.
BUNDLE = 14,
/// Lifetime markers.
LIFETIME_START = 15,
LIFETIME_END = 16,
/// A Stackmap instruction captures the location of live variables at its
/// position in the instruction stream. It is followed by a shadow of bytes
/// that must lie within the function and not contain another stackmap.
STACKMAP = 17,
/// Patchable call instruction - this instruction represents a call to a
/// constant address, followed by a series of NOPs. It is intended to
/// support optimizations for dynamic languages (such as javascript) that
/// rewrite calls to runtimes with more efficient code sequences.
/// This also implies a stack map.
PATCHPOINT = 18
};
} // end namespace TargetOpcode
} // end namespace llvm
#endif