src/Yarn/OSFiber_asm_x86.h

// Copyright 2019 The SwiftShader Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//    http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#define YARN_REG_EBX 0x00
#define YARN_REG_EBP 0x04
#define YARN_REG_ESI 0x08
#define YARN_REG_EDI 0x0c
#define YARN_REG_ESP 0x10
#define YARN_REG_EIP 0x14

#ifndef YARN_BUILD_ASM
#include <stdint.h>

// Assumes cdecl calling convention.
// Registers EAX, ECX, and EDX are caller-saved, and the rest are callee-saved.
struct yarn_fiber_context
{
    // callee-saved registers
    uintptr_t EBX;
    uintptr_t EBP;
    uintptr_t ESI;
    uintptr_t EDI;

    // stack and instruction registers
    uintptr_t ESP;
    uintptr_t EIP;
};

#ifdef __cplusplus
#include <cstddef>
static_assert(offsetof(yarn_fiber_context, EBX) == YARN_REG_EBX, "Bad register offset");
static_assert(offsetof(yarn_fiber_context, EBP) == YARN_REG_EBP, "Bad register offset");
static_assert(offsetof(yarn_fiber_context, ESI) == YARN_REG_ESI, "Bad register offset");
static_assert(offsetof(yarn_fiber_context, EDI) == YARN_REG_EDI, "Bad register offset");
static_assert(offsetof(yarn_fiber_context, ESP) == YARN_REG_ESP, "Bad register offset");
static_assert(offsetof(yarn_fiber_context, EIP) == YARN_REG_EIP, "Bad register offset");
#endif // __cplusplus

#endif // YARN_BUILD_ASM