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add gen_safe_write16, jit instr16_C7_0_mem

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This commit is contained in:
Awal Garg 2018-07-24 17:03:21 +05:30 committed by Fabian
parent dbd8c7b9fa
commit 6f45d5f6ed
3 changed files with 93 additions and 3 deletions
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78
src/rust/codegen.rs
View file

@ -334,6 +334,84 @@ pub fn gen_safe_write32(ctx: &mut JitContext, address_local: &WasmLocal, value_l
builder.free_local(phys_addr_local);
}
pub fn gen_safe_write16(ctx: &mut JitContext, address_local: &WasmLocal, value_local: &WasmLocal) {
// Generates safe_write16' fast-path inline, bailing to safe_write16_slow if necessary.
let builder = &mut ctx.builder;
//let instruction_body = &mut ctx.builder.instruction_body;
//let cpu = &mut ctx.cpu;
wasm_util::get_local(&mut builder.instruction_body, &address_local);
// Pseudo: base_on_stack = (uint32_t)address >> 12;
wasm_util::push_i32(&mut builder.instruction_body, 12);
wasm_util::shr_u32(&mut builder.instruction_body);
// scale index
wasm_util::push_i32(&mut builder.instruction_body, 2);
wasm_util::shl_i32(&mut builder.instruction_body);
// Pseudo: entry = tlb_data[base_on_stack];
let entry_local = builder.alloc_local();
wasm_util::load_aligned_i32_from_stack(
&mut builder.instruction_body,
global_pointers::TLB_DATA,
);
wasm_util::tee_local(&mut builder.instruction_body, &entry_local);
// Pseudo: bool can_use_fast_path = (entry & 0xFFF & ~TLB_GLOBAL & ~(cpl == 3 ? 0 : TLB_NO_USER) == TLB_VALID &&
// (address & 0xFFF) <= (0x1000 - 4));
wasm_util::push_i32(
&mut builder.instruction_body,
(0xFFF & !TLB_GLOBAL & !(if ctx.cpu.cpl3() { 0 } else { TLB_NO_USER })) as i32,
);
wasm_util::and_i32(&mut builder.instruction_body);
wasm_util::push_i32(&mut builder.instruction_body, TLB_VALID as i32);
wasm_util::eq_i32(&mut builder.instruction_body);
wasm_util::get_local(&mut builder.instruction_body, &address_local);
wasm_util::push_i32(&mut builder.instruction_body, 0xFFF);
wasm_util::and_i32(&mut builder.instruction_body);
wasm_util::push_i32(&mut builder.instruction_body, 0x1000 - 2);
wasm_util::le_i32(&mut builder.instruction_body);
wasm_util::and_i32(&mut builder.instruction_body);
// Pseudo:
// if(can_use_fast_path)
// {
// phys_addr = entry & ~0xFFF ^ address;
wasm_util::if_void(&mut builder.instruction_body);
wasm_util::get_local(&mut builder.instruction_body, &entry_local);
wasm_util::push_i32(&mut builder.instruction_body, !0xFFF);
wasm_util::and_i32(&mut builder.instruction_body);
wasm_util::get_local(&mut builder.instruction_body, &address_local);
wasm_util::xor_i32(&mut builder.instruction_body);
builder.free_local(entry_local);
let phys_addr_local = builder.alloc_local();
// Pseudo:
// /* continued within can_use_fast_path branch */
// mem8[phys_addr] = value;
wasm_util::tee_local(&mut builder.instruction_body, &phys_addr_local);
wasm_util::get_local(&mut builder.instruction_body, &value_local);
wasm_util::store_unaligned_u16(&mut builder.instruction_body, global_pointers::MEMORY);
// Pseudo:
// else { safe_read16_slow(address, value); }
wasm_util::else_(&mut builder.instruction_body);
wasm_util::get_local(&mut builder.instruction_body, &address_local);
wasm_util::get_local(&mut builder.instruction_body, &value_local);
gen_call_fn2(builder, "safe_write16_slow");
wasm_util::block_end(&mut builder.instruction_body);
builder.free_local(phys_addr_local);
}
pub fn gen_fn1_reg16(ctx: &mut JitContext, name: &str, r: u32) {
let fn_idx = ctx.builder.get_fn_idx(name, module_init::FN1_TYPE_INDEX);
wasm_util::load_aligned_u16(

12
src/rust/jit_instructions.rs
View file

@ -481,10 +481,16 @@ pub fn instr16_C7_0_reg_jit(ctx: &mut JitContext, r: u32, imm: u32) {
}
pub fn instr16_C7_0_mem_jit(ctx: &mut JitContext, modrm_byte: u8) {
let address_local = ctx.builder.alloc_local();
let value_local = ctx.builder.alloc_local();
codegen::gen_modrm_resolve(ctx, modrm_byte);
let imm = ctx.cpu.read_imm16() as u32;
// XXX: inline called function
codegen::gen_modrm_fn1(ctx, "instr16_C7_0_mem", imm);
wasm_util::set_local(&mut ctx.builder.instruction_body, &address_local);
let imm = ctx.cpu.read_imm16();
wasm_util::push_i32(&mut ctx.builder.instruction_body, imm as i32);
wasm_util::set_local(&mut ctx.builder.instruction_body, &value_local);
codegen::gen_safe_write16(ctx, &address_local, &value_local);
ctx.builder.free_local(address_local);
ctx.builder.free_local(value_local);
}
pub fn instr32_C7_0_reg_jit(ctx: &mut JitContext, r: u32, imm: u32) {

6
src/rust/wasmgen/wasm_util.rs
View file

@ -99,6 +99,12 @@ pub fn store_unaligned_i32(buf: &mut Vec<u8>, byte_offset: u32) {
write_leb_u32(buf, byte_offset);
}
pub fn store_unaligned_u16(buf: &mut Vec<u8>, byte_offset: u32) {
buf.push(op::OP_I32STORE16);
buf.push(op::MEM_NO_ALIGN);
write_leb_u32(buf, byte_offset);
}
pub fn shr_u32(buf: &mut Vec<u8>) { buf.push(op::OP_I32SHRU); }
pub fn shr_i32(buf: &mut Vec<u8>) { buf.push(op::OP_I32SHRS); }