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//===-- llvm/CallingConv.h - LLVM Calling Conventions -----------*- 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 a set of enums which specify the assigned numeric values
// for known llvm calling conventions.


namespace llvm {

/// CallingConv Namespace - This namespace contains an enum with a value for
/// the well-known calling conventions.
namespace CallingConv {
  enum ID {
    // C - The default llvm calling convention, compatible with C.  This
    // convention is the only calling convention that supports varargs calls.
    // As with typical C calling conventions, the callee/caller have to tolerate
    // certain amounts of prototype mismatch.
    C = 0,
    /// CSRet - C Struct Return calling convention.  This convention requires
    /// that the function return void and take a pointer as the first argument
    /// of the struct.  This is used by targets which need to distinguish
    /// between C functions returning a structure, and C functions taking a
    /// structure pointer as the first argument to the function.
    CSRet = 1,

    // Generic LLVM calling conventions.  None of these calling conventions
    // support varargs calls, and all assume that the caller and callee
    // prototype exactly match.

    // Fast - This calling convention attempts to make calls as fast as possible
    // (e.g. by passing things in registers).
    Fast = 8,

    // Cold - This calling convention attempts to make code in the caller as
    // efficient as possible under the assumption that the call is not commonly
    // executed.  As such, these calls often preserve all registers so that the
    // call does not break any live ranges in the caller side.
    Cold = 9,

    // Target - This is the start of the target-specific calling conventions,
    // e.g. fastcall and thiscall on X86.
    FirstTargetCC = 64
} // End CallingConv namespace

} // End llvm namespace