include/llvm/IR/CallingConv.h

   1 //===- llvm/CallingConv.h - LLVM Calling Conventions ------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file defines LLVM's set of calling conventions.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef LLVM_IR_CALLINGCONV_H
  14 #define LLVM_IR_CALLINGCONV_H
  15
  16 namespace llvm {
  17
  18 /// CallingConv Namespace - This namespace contains an enum with a value for
  19 /// the well-known calling conventions.
  20 ///
  21 namespace CallingConv {
  22
  23   /// LLVM IR allows to use arbitrary numbers as calling convention identifiers.
  24   using ID = unsigned;
  25
  26   /// A set of enums which specify the assigned numeric values for known llvm
  27   /// calling conventions.
  28   /// LLVM Calling Convention Representation
  29   enum {
  30     /// C - The default llvm calling convention, compatible with C.  This
  31     /// convention is the only calling convention that supports varargs calls.
  32     /// As with typical C calling conventions, the callee/caller have to
  33     /// tolerate certain amounts of prototype mismatch.
  34     C = 0,
  35
  36     // Generic LLVM calling conventions.  None of these calling conventions
  37     // support varargs calls, and all assume that the caller and callee
  38     // prototype exactly match.
  39
  40     /// Fast - This calling convention attempts to make calls as fast as
  41     /// possible (e.g. by passing things in registers).
  42     Fast = 8,
  43
  44     // Cold - This calling convention attempts to make code in the caller as
  45     // efficient as possible under the assumption that the call is not commonly
  46     // executed.  As such, these calls often preserve all registers so that the
  47     // call does not break any live ranges in the caller side.
  48     Cold = 9,
  49
  50     // GHC - Calling convention used by the Glasgow Haskell Compiler (GHC).
  51     GHC = 10,
  52
  53     // HiPE - Calling convention used by the High-Performance Erlang Compiler
  54     // (HiPE).
  55     HiPE = 11,
  56
  57     // WebKit JS - Calling convention for stack based JavaScript calls
  58     WebKit_JS = 12,
  59
  60     // AnyReg - Calling convention for dynamic register based calls (e.g.
  61     // stackmap and patchpoint intrinsics).
  62     AnyReg = 13,
  63
  64     // PreserveMost - Calling convention for runtime calls that preserves most
  65     // registers.
  66     PreserveMost = 14,
  67
  68     // PreserveAll - Calling convention for runtime calls that preserves
  69     // (almost) all registers.
  70     PreserveAll = 15,
  71
  72     // Swift - Calling convention for Swift.
  73     Swift = 16,
  74
  75     // CXX_FAST_TLS - Calling convention for access functions.
  76     CXX_FAST_TLS = 17,
  77
  78     /// Tail - This calling convention attemps to make calls as fast as
  79     /// possible while guaranteeing that tail call optimization can always
  80     /// be performed.
  81     Tail = 18,
  82
  83     // Target - This is the start of the target-specific calling conventions,
  84     // e.g. fastcall and thiscall on X86.
  85     FirstTargetCC = 64,
  86
  87     /// X86_StdCall - stdcall is the calling conventions mostly used by the
  88     /// Win32 API. It is basically the same as the C convention with the
  89     /// difference in that the callee is responsible for popping the arguments
  90     /// from the stack.
  91     X86_StdCall = 64,
  92
  93     /// X86_FastCall - 'fast' analog of X86_StdCall. Passes first two arguments
  94     /// in ECX:EDX registers, others - via stack. Callee is responsible for
  95     /// stack cleaning.
  96     X86_FastCall = 65,
  97
  98     /// ARM_APCS - ARM Procedure Calling Standard calling convention (obsolete,
  99     /// but still used on some targets).
 100     ARM_APCS = 66,
 101
 102     /// ARM_AAPCS - ARM Architecture Procedure Calling Standard calling
 103     /// convention (aka EABI). Soft float variant.
 104     ARM_AAPCS = 67,
 105
 106     /// ARM_AAPCS_VFP - Same as ARM_AAPCS, but uses hard floating point ABI.
 107     ARM_AAPCS_VFP = 68,
 108
 109     /// MSP430_INTR - Calling convention used for MSP430 interrupt routines.
 110     MSP430_INTR = 69,
 111
 112     /// X86_ThisCall - Similar to X86_StdCall. Passes first argument in ECX,
 113     /// others via stack. Callee is responsible for stack cleaning. MSVC uses
 114     /// this by default for methods in its ABI.
 115     X86_ThisCall = 70,
 116
 117     /// PTX_Kernel - Call to a PTX kernel.
 118     /// Passes all arguments in parameter space.
 119     PTX_Kernel = 71,
 120
 121     /// PTX_Device - Call to a PTX device function.
 122     /// Passes all arguments in register or parameter space.
 123     PTX_Device = 72,
 124
 125     /// SPIR_FUNC - Calling convention for SPIR non-kernel device functions.
 126     /// No lowering or expansion of arguments.
 127     /// Structures are passed as a pointer to a struct with the byval attribute.
 128     /// Functions can only call SPIR_FUNC and SPIR_KERNEL functions.
 129     /// Functions can only have zero or one return values.
 130     /// Variable arguments are not allowed, except for printf.
 131     /// How arguments/return values are lowered are not specified.
 132     /// Functions are only visible to the devices.
 133     SPIR_FUNC = 75,
 134
 135     /// SPIR_KERNEL - Calling convention for SPIR kernel functions.
 136     /// Inherits the restrictions of SPIR_FUNC, except
 137     /// Cannot have non-void return values.
 138     /// Cannot have variable arguments.
 139     /// Can also be called by the host.
 140     /// Is externally visible.
 141     SPIR_KERNEL = 76,
 142
 143     /// Intel_OCL_BI - Calling conventions for Intel OpenCL built-ins
 144     Intel_OCL_BI = 77,
 145
 146     /// The C convention as specified in the x86-64 supplement to the
 147     /// System V ABI, used on most non-Windows systems.
 148     X86_64_SysV = 78,
 149
 150     /// The C convention as implemented on Windows/x86-64 and
 151     /// AArch64. This convention differs from the more common
 152     /// \c X86_64_SysV convention in a number of ways, most notably in
 153     /// that XMM registers used to pass arguments are shadowed by GPRs,
 154     /// and vice versa.
 155     /// On AArch64, this is identical to the normal C (AAPCS) calling
 156     /// convention for normal functions, but floats are passed in integer
 157     /// registers to variadic functions.
 158     Win64 = 79,
 159
 160     /// MSVC calling convention that passes vectors and vector aggregates
 161     /// in SSE registers.
 162     X86_VectorCall = 80,
 163
 164     /// Calling convention used by HipHop Virtual Machine (HHVM) to
 165     /// perform calls to and from translation cache, and for calling PHP
 166     /// functions.
 167     /// HHVM calling convention supports tail/sibling call elimination.
 168     HHVM = 81,
 169
 170     /// HHVM calling convention for invoking C/C++ helpers.
 171     HHVM_C = 82,
 172
 173     /// X86_INTR - x86 hardware interrupt context. Callee may take one or two
 174     /// parameters, where the 1st represents a pointer to hardware context frame
 175     /// and the 2nd represents hardware error code, the presence of the later
 176     /// depends on the interrupt vector taken. Valid for both 32- and 64-bit
 177     /// subtargets.
 178     X86_INTR = 83,
 179
 180     /// Used for AVR interrupt routines.
 181     AVR_INTR = 84,
 182
 183     /// Calling convention used for AVR signal routines.
 184     AVR_SIGNAL = 85,
 185
 186     /// Calling convention used for special AVR rtlib functions
 187     /// which have an "optimized" convention to preserve registers.
 188     AVR_BUILTIN = 86,
 189
 190     /// Calling convention used for Mesa vertex shaders, or AMDPAL last shader
 191     /// stage before rasterization (vertex shader if tessellation and geometry
 192     /// are not in use, or otherwise copy shader if one is needed).
 193     AMDGPU_VS = 87,
 194
 195     /// Calling convention used for Mesa/AMDPAL geometry shaders.
 196     AMDGPU_GS = 88,
 197
 198     /// Calling convention used for Mesa/AMDPAL pixel shaders.
 199     AMDGPU_PS = 89,
 200
 201     /// Calling convention used for Mesa/AMDPAL compute shaders.
 202     AMDGPU_CS = 90,
 203
 204     /// Calling convention for AMDGPU code object kernels.
 205     AMDGPU_KERNEL = 91,
 206
 207     /// Register calling convention used for parameters transfer optimization
 208     X86_RegCall = 92,
 209
 210     /// Calling convention used for Mesa/AMDPAL hull shaders (= tessellation
 211     /// control shaders).
 212     AMDGPU_HS = 93,
 213
 214     /// Calling convention used for special MSP430 rtlib functions
 215     /// which have an "optimized" convention using additional registers.
 216     MSP430_BUILTIN = 94,
 217
 218     /// Calling convention used for AMDPAL vertex shader if tessellation is in
 219     /// use.
 220     AMDGPU_LS = 95,
 221
 222     /// Calling convention used for AMDPAL shader stage before geometry shader
 223     /// if geometry is in use. So either the domain (= tessellation evaluation)
 224     /// shader if tessellation is in use, or otherwise the vertex shader.
 225     AMDGPU_ES = 96,
 226
 227     // Calling convention between AArch64 Advanced SIMD functions
 228     AArch64_VectorCall = 97,
 229
 230     /// Calling convention between AArch64 SVE functions
 231     AArch64_SVE_VectorCall = 98,
 232
 233     /// Calling convention for emscripten __invoke_* functions. The first
 234     /// argument is required to be the function ptr being indirectly called.
 235     /// The remainder matches the regular calling convention.
 236     WASM_EmscriptenInvoke = 99,
 237
 238     /// The highest possible calling convention ID. Must be some 2^k - 1.
 239     MaxID = 1023
 240   };
 241
 242 } // end namespace CallingConv
 243
 244 } // end namespace llvm
 245
 246 #endif // LLVM_IR_CALLINGCONV_H