v86/gen/generate_analyzer.js

487 lines
14 KiB
JavaScript
Executable file

#!/usr/bin/env node
"use strict";
const assert = require("assert").strict;
const fs = require("fs");
const path = require("path");
const x86_table = require("./x86_table");
const rust_ast = require("./rust_ast");
const { hex, mkdirpSync, get_switch_value, get_switch_exist, finalize_table_rust } = require("./util");
const OUT_DIR = path.join(__dirname, "..", "src/rust/gen/");
mkdirpSync(OUT_DIR);
const table_arg = get_switch_value("--table");
const gen_all = get_switch_exist("--all");
const to_generate = {
analyzer: gen_all || table_arg === "analyzer",
analyzer0f: gen_all || table_arg === "analyzer0f",
};
assert(
Object.keys(to_generate).some(k => to_generate[k]),
"Pass --table [analyzer|analyzer0f] or --all to pick which tables to generate"
);
gen_table();
function gen_read_imm_call(op, size_variant)
{
let size = (op.os || op.opcode % 2 === 1) ? size_variant : 8;
if(op.imm8 || op.imm8s || op.imm16 || op.imm1632 || op.imm32 || op.immaddr)
{
if(op.imm8)
{
return "cpu.read_imm8()";
}
else if(op.imm8s)
{
return "cpu.read_imm8s()";
}
else
{
if(op.immaddr)
{
// immaddr: depends on address size
return "cpu.read_moffs()";
}
else
{
assert(op.imm1632 || op.imm16 || op.imm32);
if(op.imm1632 && size === 16 || op.imm16)
{
return "cpu.read_imm16()";
}
else
{
assert(op.imm1632 && size === 32 || op.imm32);
return "cpu.read_imm32()";
}
}
}
}
else
{
return undefined;
}
}
function gen_call(name, args)
{
args = args || [];
return `${name}(${args.join(", ")});`;
}
/*
* Current naming scheme:
* instr(16|32|)_(66|F2|F3)?0F?[0-9a-f]{2}(_[0-7])?(_mem|_reg|)
*/
function make_instruction_name(encoding, size)
{
const suffix = encoding.os ? String(size) : "";
const opcode_hex = hex(encoding.opcode & 0xFF, 2);
const first_prefix = (encoding.opcode & 0xFF00) === 0 ? "" : hex(encoding.opcode >> 8 & 0xFF, 2);
const second_prefix = (encoding.opcode & 0xFF0000) === 0 ? "" : hex(encoding.opcode >> 16 & 0xFF, 2);
const fixed_g_suffix = encoding.fixed_g === undefined ? "" : `_${encoding.fixed_g}`;
assert(first_prefix === "" || first_prefix === "0F" || first_prefix === "F2" || first_prefix === "F3");
assert(second_prefix === "" || second_prefix === "66" || second_prefix === "F2" || second_prefix === "F3");
return `instr${suffix}_${second_prefix}${first_prefix}${opcode_hex}${fixed_g_suffix}`;
}
function gen_instruction_body(encodings, size)
{
const encoding = encodings[0];
let has_66 = [];
let has_F2 = [];
let has_F3 = [];
let no_prefix = [];
for(let e of encodings)
{
if((e.opcode >>> 16) === 0x66) has_66.push(e);
else if((e.opcode >>> 8 & 0xFF) === 0xF2 || (e.opcode >>> 16) === 0xF2) has_F2.push(e);
else if((e.opcode >>> 8 & 0xFF) === 0xF3 || (e.opcode >>> 16) === 0xF3) has_F3.push(e);
else no_prefix.push(e);
}
if(has_F2.length || has_F3.length)
{
assert((encoding.opcode & 0xFF0000) === 0 || (encoding.opcode & 0xFF00) === 0x0F00);
}
if(has_66.length)
{
assert((encoding.opcode & 0xFF00) === 0x0F00);
}
const code = [];
if(encoding.e)
{
code.push("let modrm_byte = cpu.read_imm8();");
}
if(has_66.length || has_F2.length || has_F3.length)
{
const if_blocks = [];
if(has_66.length) {
const body = gen_instruction_body_after_prefix(has_66, size);
if_blocks.push({ condition: "cpu.prefixes & ::prefix::PREFIX_66 != 0", body, });
}
if(has_F2.length) {
const body = gen_instruction_body_after_prefix(has_F2, size);
if_blocks.push({ condition: "cpu.prefixes & ::prefix::PREFIX_F2 != 0", body, });
}
if(has_F3.length) {
const body = gen_instruction_body_after_prefix(has_F3, size);
if_blocks.push({ condition: "cpu.prefixes & ::prefix::PREFIX_F3 != 0", body, });
}
const else_block = {
body: gen_instruction_body_after_prefix(no_prefix, size),
};
return [].concat(
code,
{
type: "if-else",
if_blocks,
else_block,
}
);
}
else {
return [].concat(
code,
gen_instruction_body_after_prefix(encodings, size)
);
}
}
function gen_instruction_body_after_prefix(encodings, size)
{
const encoding = encodings[0];
if(encoding.fixed_g !== undefined)
{
assert(encoding.e);
// instruction with modrm byte where the middle 3 bits encode the instruction
// group by opcode without prefix plus middle bits of modrm byte
let cases = encodings.reduce((cases_by_opcode, case_) => {
assert(typeof case_.fixed_g === "number");
cases_by_opcode[case_.opcode & 0xFFFF | case_.fixed_g << 16] = case_;
return cases_by_opcode;
}, Object.create(null));
cases = Object.values(cases).sort((e1, e2) => e1.fixed_g - e2.fixed_g);
return [
{
type: "switch",
condition: "modrm_byte >> 3 & 7",
cases: cases.map(case_ => {
const fixed_g = case_.fixed_g;
const body = gen_instruction_body_after_fixed_g(case_, size);
return {
conditions: [fixed_g],
body,
};
}),
default_case: {
body: [
"analysis.ty = ::analysis::AnalysisType::BlockBoundary;",
"analysis.no_next_instruction = true;",
],
}
},
];
}
else {
assert(encodings.length === 1);
return gen_instruction_body_after_fixed_g(encodings[0], size);
}
}
function gen_instruction_body_after_fixed_g(encoding, size)
{
const imm_read = gen_read_imm_call(encoding, size);
const instruction_postfix = [];
if(encoding.custom_sti) {
instruction_postfix.push("analysis.ty = ::analysis::AnalysisType::STI;");
}
else if(
encoding.block_boundary &&
// jump_offset_imm: Is a block boundary, but gets a different type (Jump) below
!encoding.jump_offset_imm || (!encoding.custom && encoding.e))
{
instruction_postfix.push("analysis.ty = ::analysis::AnalysisType::BlockBoundary;");
}
if(encoding.no_next_instruction)
{
instruction_postfix.push("analysis.no_next_instruction = true;");
}
if(encoding.absolute_jump)
{
instruction_postfix.push("analysis.absolute_jump = true;");
}
if(encoding.prefix)
{
const instruction_name = "::analysis::" + make_instruction_name(encoding, size) + "_analyze";
const args = ["cpu", "analysis"];
assert(!imm_read);
return [].concat(
gen_call(instruction_name, args),
instruction_postfix
);
}
else if(encoding.e)
{
// instruction with modrm byte where the middle 3 bits encode a register
const reg_postfix = [];
const mem_postfix = [];
if(encoding.mem_ud)
{
mem_postfix.push(
"analysis.ty = ::analysis::AnalysisType::BlockBoundary;"
);
}
if(encoding.reg_ud)
{
reg_postfix.push(
"analysis.ty = ::analysis::AnalysisType::BlockBoundary;"
);
}
if(encoding.ignore_mod)
{
assert(!imm_read, "Unexpected instruction (ignore mod with immediate value)");
// Has modrm byte, but the 2 mod bits are ignored and both
// operands are always registers (0f20-0f24)
return instruction_postfix;
}
else
{
return [].concat(
{
type: "if-else",
if_blocks: [{
condition: "modrm_byte < 0xC0",
body: [].concat(
gen_call("::analysis::modrm_analyze", ["cpu", "modrm_byte"]),
mem_postfix,
),
}],
else_block: {
body: reg_postfix,
},
},
imm_read ? [imm_read + ";"] : [],
instruction_postfix
);
}
}
else
{
// instruction without modrm byte or prefix
const body = [];
if(imm_read)
{
if(encoding.jump_offset_imm)
{
body.push("let jump_offset = " + imm_read + ";");
if(encoding.conditional_jump)
{
assert(
(encoding.opcode & ~0xF) === 0x70 ||
(encoding.opcode & ~0xF) === 0x0F80 ||
(encoding.opcode & ~0x3) === 0xE0
);
const condition_index = encoding.opcode & 0xFF;
body.push(`analysis.ty = ::analysis::AnalysisType::Jump { offset: jump_offset as i32, condition: Some(0x${hex(condition_index, 2)}), is_32: cpu.osize_32() };`);
}
else
{
body.push(`analysis.ty = ::analysis::AnalysisType::Jump { offset: jump_offset as i32, condition: None, is_32: cpu.osize_32() };`);
}
}
else
{
body.push(imm_read + ";");
}
}
if(encoding.extra_imm16)
{
assert(imm_read);
body.push(gen_call("cpu.read_imm16"));
}
else if(encoding.extra_imm8)
{
assert(imm_read);
body.push(gen_call("cpu.read_imm8"));
}
return [].concat(
body,
instruction_postfix
);
}
}
function gen_table()
{
let by_opcode = Object.create(null);
let by_opcode0f = Object.create(null);
for(let o of x86_table)
{
let opcode = o.opcode;
if((opcode & 0xFF00) === 0x0F00)
{
opcode &= 0xFF;
by_opcode0f[opcode] = by_opcode0f[opcode] || [];
by_opcode0f[opcode].push(o);
}
else
{
opcode &= 0xFF;
by_opcode[opcode] = by_opcode[opcode] || [];
by_opcode[opcode].push(o);
}
}
let cases = [];
for(let opcode = 0; opcode < 0x100; opcode++)
{
let encoding = by_opcode[opcode];
assert(encoding && encoding.length);
let opcode_hex = hex(opcode, 2);
let opcode_high_hex = hex(opcode | 0x100, 2);
if(encoding[0].os)
{
cases.push({
conditions: [`0x${opcode_hex}`],
body: gen_instruction_body(encoding, 16),
});
cases.push({
conditions: [`0x${opcode_high_hex}`],
body: gen_instruction_body(encoding, 32),
});
}
else
{
cases.push({
conditions: [`0x${opcode_hex}`, `0x${opcode_high_hex}`],
body: gen_instruction_body(encoding, undefined),
});
}
}
const table = {
type: "switch",
condition: "opcode",
cases,
default_case: {
body: ["dbg_assert!(false);"]
},
};
if(to_generate.analyzer)
{
const code = [
"#[cfg_attr(rustfmt, rustfmt_skip)]",
"pub fn analyzer(opcode: u32, cpu: &mut ::cpu_context::CpuContext, analysis: &mut ::analysis::Analysis) {",
table,
"}",
];
finalize_table_rust(
OUT_DIR,
"analyzer.rs",
rust_ast.print_syntax_tree([].concat(code)).join("\n") + "\n"
);
}
const cases0f = [];
for(let opcode = 0; opcode < 0x100; opcode++)
{
let encoding = by_opcode0f[opcode];
assert(encoding && encoding.length);
let opcode_hex = hex(opcode, 2);
let opcode_high_hex = hex(opcode | 0x100, 2);
if(encoding[0].os)
{
cases0f.push({
conditions: [`0x${opcode_hex}`],
body: gen_instruction_body(encoding, 16),
});
cases0f.push({
conditions: [`0x${opcode_high_hex}`],
body: gen_instruction_body(encoding, 32),
});
}
else
{
let block = {
conditions: [`0x${opcode_hex}`, `0x${opcode_high_hex}`],
body: gen_instruction_body(encoding, undefined),
};
cases0f.push(block);
}
}
const table0f = {
type: "switch",
condition: "opcode",
cases: cases0f,
default_case: {
body: ["dbg_assert!(false);"]
},
};
if(to_generate.analyzer0f)
{
const code = [
"#![allow(unused)]",
"#[cfg_attr(rustfmt, rustfmt_skip)]",
"pub fn analyzer(opcode: u32, cpu: &mut ::cpu_context::CpuContext, analysis: &mut ::analysis::Analysis) {",
table0f,
"}"
];
finalize_table_rust(
OUT_DIR,
"analyzer0f.rs",
rust_ast.print_syntax_tree([].concat(code)).join("\n") + "\n"
);
}
}