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 /// Special calling convention on Windows for calling the Control 84 /// Guard Check ICall funtion. The function takes exactly one argument 85 /// (address of the target function) passed in the first argument register, 86 /// and has no return value. All register values are preserved. 87 CFGuard_Check = 19, 88 89 /// SwiftTail - This follows the Swift calling convention in how arguments 90 /// are passed but guarantees tail calls will be made by making the callee 91 /// clean up their stack. 92 SwiftTail = 20, 93 94 // Target - This is the start of the target-specific calling conventions, 95 // e.g. fastcall and thiscall on X86. 96 FirstTargetCC = 64, 97 98 /// X86_StdCall - stdcall is the calling conventions mostly used by the 99 /// Win32 API. It is basically the same as the C convention with the 100 /// difference in that the callee is responsible for popping the arguments 101 /// from the stack. 102 X86_StdCall = 64, 103 104 /// X86_FastCall - 'fast' analog of X86_StdCall. Passes first two arguments 105 /// in ECX:EDX registers, others - via stack. Callee is responsible for 106 /// stack cleaning. 107 X86_FastCall = 65, 108 109 /// ARM_APCS - ARM Procedure Calling Standard calling convention (obsolete, 110 /// but still used on some targets). 111 ARM_APCS = 66, 112 113 /// ARM_AAPCS - ARM Architecture Procedure Calling Standard calling 114 /// convention (aka EABI). Soft float variant. 115 ARM_AAPCS = 67, 116 117 /// ARM_AAPCS_VFP - Same as ARM_AAPCS, but uses hard floating point ABI. 118 ARM_AAPCS_VFP = 68, 119 120 /// MSP430_INTR - Calling convention used for MSP430 interrupt routines. 121 MSP430_INTR = 69, 122 123 /// X86_ThisCall - Similar to X86_StdCall. Passes first argument in ECX, 124 /// others via stack. Callee is responsible for stack cleaning. MSVC uses 125 /// this by default for methods in its ABI. 126 X86_ThisCall = 70, 127 128 /// PTX_Kernel - Call to a PTX kernel. 129 /// Passes all arguments in parameter space. 130 PTX_Kernel = 71, 131 132 /// PTX_Device - Call to a PTX device function. 133 /// Passes all arguments in register or parameter space. 134 PTX_Device = 72, 135 136 /// SPIR_FUNC - Calling convention for SPIR non-kernel device functions. 137 /// No lowering or expansion of arguments. 138 /// Structures are passed as a pointer to a struct with the byval attribute. 139 /// Functions can only call SPIR_FUNC and SPIR_KERNEL functions. 140 /// Functions can only have zero or one return values. 141 /// Variable arguments are not allowed, except for printf. 142 /// How arguments/return values are lowered are not specified. 143 /// Functions are only visible to the devices. 144 SPIR_FUNC = 75, 145 146 /// SPIR_KERNEL - Calling convention for SPIR kernel functions. 147 /// Inherits the restrictions of SPIR_FUNC, except 148 /// Cannot have non-void return values. 149 /// Cannot have variable arguments. 150 /// Can also be called by the host. 151 /// Is externally visible. 152 SPIR_KERNEL = 76, 153 154 /// Intel_OCL_BI - Calling conventions for Intel OpenCL built-ins 155 Intel_OCL_BI = 77, 156 157 /// The C convention as specified in the x86-64 supplement to the 158 /// System V ABI, used on most non-Windows systems. 159 X86_64_SysV = 78, 160 161 /// The C convention as implemented on Windows/x86-64 and 162 /// AArch64. This convention differs from the more common 163 /// \c X86_64_SysV convention in a number of ways, most notably in 164 /// that XMM registers used to pass arguments are shadowed by GPRs, 165 /// and vice versa. 166 /// On AArch64, this is identical to the normal C (AAPCS) calling 167 /// convention for normal functions, but floats are passed in integer 168 /// registers to variadic functions. 169 Win64 = 79, 170 171 /// MSVC calling convention that passes vectors and vector aggregates 172 /// in SSE registers. 173 X86_VectorCall = 80, 174 175 /// Calling convention used by HipHop Virtual Machine (HHVM) to 176 /// perform calls to and from translation cache, and for calling PHP 177 /// functions. 178 /// HHVM calling convention supports tail/sibling call elimination. 179 HHVM = 81, 180 181 /// HHVM calling convention for invoking C/C++ helpers. 182 HHVM_C = 82, 183 184 /// X86_INTR - x86 hardware interrupt context. Callee may take one or two 185 /// parameters, where the 1st represents a pointer to hardware context frame 186 /// and the 2nd represents hardware error code, the presence of the later 187 /// depends on the interrupt vector taken. Valid for both 32- and 64-bit 188 /// subtargets. 189 X86_INTR = 83, 190 191 /// Used for AVR interrupt routines. 192 AVR_INTR = 84, 193 194 /// Calling convention used for AVR signal routines. 195 AVR_SIGNAL = 85, 196 197 /// Calling convention used for special AVR rtlib functions 198 /// which have an "optimized" convention to preserve registers. 199 AVR_BUILTIN = 86, 200 201 /// Calling convention used for Mesa vertex shaders, or AMDPAL last shader 202 /// stage before rasterization (vertex shader if tessellation and geometry 203 /// are not in use, or otherwise copy shader if one is needed). 204 AMDGPU_VS = 87, 205 206 /// Calling convention used for Mesa/AMDPAL geometry shaders. 207 AMDGPU_GS = 88, 208 209 /// Calling convention used for Mesa/AMDPAL pixel shaders. 210 AMDGPU_PS = 89, 211 212 /// Calling convention used for Mesa/AMDPAL compute shaders. 213 AMDGPU_CS = 90, 214 215 /// Calling convention for AMDGPU code object kernels. 216 AMDGPU_KERNEL = 91, 217 218 /// Register calling convention used for parameters transfer optimization 219 X86_RegCall = 92, 220 221 /// Calling convention used for Mesa/AMDPAL hull shaders (= tessellation 222 /// control shaders). 223 AMDGPU_HS = 93, 224 225 /// Calling convention used for special MSP430 rtlib functions 226 /// which have an "optimized" convention using additional registers. 227 MSP430_BUILTIN = 94, 228 229 /// Calling convention used for AMDPAL vertex shader if tessellation is in 230 /// use. 231 AMDGPU_LS = 95, 232 233 /// Calling convention used for AMDPAL shader stage before geometry shader 234 /// if geometry is in use. So either the domain (= tessellation evaluation) 235 /// shader if tessellation is in use, or otherwise the vertex shader. 236 AMDGPU_ES = 96, 237 238 // Calling convention between AArch64 Advanced SIMD functions 239 AArch64_VectorCall = 97, 240 241 /// Calling convention between AArch64 SVE functions 242 AArch64_SVE_VectorCall = 98, 243 244 /// Calling convention for emscripten __invoke_* functions. The first 245 /// argument is required to be the function ptr being indirectly called. 246 /// The remainder matches the regular calling convention. 247 WASM_EmscriptenInvoke = 99, 248 249 /// Calling convention used for AMD graphics targets. 250 AMDGPU_Gfx = 100, 251 252 /// M68k_INTR - Calling convention used for M68k interrupt routines. 253 M68k_INTR = 101, 254 255 /// The highest possible calling convention ID. Must be some 2^k - 1. 256 MaxID = 1023 257 }; 258 259 } // end namespace CallingConv 260 261 } // end namespace llvm 262 263 #endif // LLVM_IR_CALLINGCONV_H 264