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Add FuncEnvironment trait.

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This trait is used to provide the environment necessary to translate a
single WebAssembly function without having other global data structures
for the WebAssembly module.

The WasmRuntime trait extends the FuncEnvironment trait for those uses
that want to parse a whole WebAssembly module.

- Change the handling of WebAssembly globals to use the FuncEnvironment
  trait as well as the new GlobalVar infrastructure in Cretonne. The
  runtime is not consulted on the translation of each
  get_global/get_global instruction. Instead it gets to create the
  GlobalVar declaration in the function preamble the first time the
  global is used.

- Change the handling of heap load/store instructions to use the new
  Heap infrastructure in Cretonne. The runtime is called to create the
  Heap declaration in the preamble. It is not involved in individual
  load/store instructions.
This commit is contained in:
Jakob Stoklund Olesen
2017-09-05 13:11:35 -07:00
parent 19c8ba5021
commit 0ac1d0dd94
6 changed files with 240 additions and 190 deletions
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265
lib/wasm/src/code_translator.rs
View File

@@ -21,18 +21,18 @@
//!
//! That is why `translate_function_body` takes an object having the `WasmRuntime` trait as
//! argument.
use cretonne::ir::{Function, Signature, Type, InstBuilder, FunctionName, Ebb, FuncRef, SigRef,
ExtFuncData, MemFlags};
use cretonne::ir::{self, Function, Signature, Type, InstBuilder, FunctionName, Ebb, FuncRef,
SigRef, ExtFuncData, MemFlags};
use cretonne::ir::types::*;
use cretonne::ir::immediates::{Ieee32, Ieee64, Offset32};
use cretonne::ir::immediates::{Ieee32, Ieee64};
use cretonne::ir::condcodes::{IntCC, FloatCC};
use cton_frontend::{ILBuilder, FunctionBuilder};
use wasmparser::{Parser, ParserState, Operator, WasmDecoder, MemoryImmediate};
use translation_utils::{f32_translation, f64_translation, type_to_type, translate_type, Local,
GlobalIndex, FunctionIndex, SignatureIndex};
FunctionIndex, SignatureIndex};
use state::{TranslationState, ControlStackFrame};
use std::collections::HashMap;
use runtime::WasmRuntime;
use runtime::{FuncEnvironment, GlobalValue, WasmRuntime};
use std::u32;
@@ -194,12 +194,28 @@ fn translate_operator(
* `get_global` and `set_global` are handled by the runtime.
***********************************************************************************/
Operator::GetGlobal { global_index } => {
let val = runtime.translate_get_global(builder, global_index as GlobalIndex);
let val = match state.get_global(builder.func, global_index, runtime) {
GlobalValue::Const(val) => val,
GlobalValue::Memory { gv, ty } => {
let addr = builder.ins().global_addr(runtime.native_pointer(), gv);
// TODO: It is likely safe to set `aligned notrap` flags on a global load.
let flags = ir::MemFlags::new();
builder.ins().load(ty, flags, addr, 0)
}
};
state.push1(val);
}
Operator::SetGlobal { global_index } => {
let val = state.pop1();
runtime.translate_set_global(builder, global_index as GlobalIndex, val);
match state.get_global(builder.func, global_index, runtime) {
GlobalValue::Const(_) => panic!("global #{} is a constant", global_index),
GlobalValue::Memory { gv, .. } => {
let addr = builder.ins().global_addr(runtime.native_pointer(), gv);
// TODO: It is likely safe to set `aligned notrap` flags on a global store.
let flags = ir::MemFlags::new();
let val = state.pop1();
builder.ins().store(flags, val, addr, 0);
}
}
}
/********************************* Stack misc ***************************************
* `drop`, `nop`, `unreachable` and `select`.
@@ -508,130 +524,46 @@ fn translate_operator(
* TODO: differentiate between 32 bit and 64 bit architecture, to put the uextend or not
************************************************************************************/
Operator::I32Load8U { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().uload8(I32, memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Uload8, I32, builder, state, runtime);
}
Operator::I32Load16U { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().uload8(I32, memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Uload16, I32, builder, state, runtime);
}
Operator::I32Load8S { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().sload8(I32, memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Sload8, I32, builder, state, runtime);
}
Operator::I32Load16S { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().sload8(I32, memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Sload16, I32, builder, state, runtime);
}
Operator::I64Load8U { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().uload8(I64, memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Uload8, I64, builder, state, runtime);
}
Operator::I64Load16U { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().uload16(I64, memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Uload16, I64, builder, state, runtime);
}
Operator::I64Load8S { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().sload8(I64, memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Sload8, I64, builder, state, runtime);
}
Operator::I64Load16S { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().sload16(I64, memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Sload16, I64, builder, state, runtime);
}
Operator::I64Load32S { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().sload32(memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Sload32, I64, builder, state, runtime);
}
Operator::I64Load32U { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().uload32(memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Uload32, I64, builder, state, runtime);
}
Operator::I32Load { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().load(I32, memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Load, I32, builder, state, runtime);
}
Operator::F32Load { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().load(F32, memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Load, F32, builder, state, runtime);
}
Operator::I64Load { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().load(I64, memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Load, I64, builder, state, runtime);
}
Operator::F64Load { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
state.push1(builder.ins().load(F64, memflags, addr, memoffset))
translate_load(offset, ir::Opcode::Load, F64, builder, state, runtime);
}
/****************************** Store instructions ***********************************
* Wasm specifies an integer alignment flag but we drop it in Cretonne.
@@ -642,46 +574,18 @@ fn translate_operator(
Operator::I64Store { memory_immediate: MemoryImmediate { flags: _, offset } } |
Operator::F32Store { memory_immediate: MemoryImmediate { flags: _, offset } } |
Operator::F64Store { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let val = state.pop1();
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
builder.ins().store(memflags, val, addr, memoffset);
translate_store(offset, ir::Opcode::Store, builder, state, runtime);
}
Operator::I32Store8 { memory_immediate: MemoryImmediate { flags: _, offset } } |
Operator::I64Store8 { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let val = state.pop1();
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
builder.ins().istore8(memflags, val, addr, memoffset);
translate_store(offset, ir::Opcode::Istore8, builder, state, runtime);
}
Operator::I32Store16 { memory_immediate: MemoryImmediate { flags: _, offset } } |
Operator::I64Store16 { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let val = state.pop1();
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
builder.ins().istore16(memflags, val, addr, memoffset);
translate_store(offset, ir::Opcode::Istore16, builder, state, runtime);
}
Operator::I64Store32 { memory_immediate: MemoryImmediate { flags: _, offset } } => {
let val = state.pop1();
let address_i32 = state.pop1();
let base = runtime.translate_memory_base_address(builder, 0);
let address_i64 = builder.ins().uextend(I64, address_i32);
let addr = builder.ins().iadd(base, address_i64);
let memflags = MemFlags::new();
let memoffset = Offset32::new(offset as i32);
builder.ins().istore32(memflags, val, addr, memoffset);
translate_store(offset, ir::Opcode::Istore32, builder, state, runtime);
}
/****************************** Nullary Operators ************************************/
Operator::I32Const { value } => state.push1(builder.ins().iconst(I32, value as i64)),
@@ -1117,6 +1021,91 @@ fn translate_unreachable_operator(
}
}
// Get the address+offset to use for a heap access.
fn get_heap_addr(
heap: ir::Heap,
addr32: ir::Value,
offset: u32,
addr_ty: ir::Type,
builder: &mut FunctionBuilder<Local>,
) -> (ir::Value, i32) {
use std::cmp::min;
let guard_size: i64 = builder.func.heaps[heap].guard_size.into();
assert!(guard_size > 0, "Heap guard pages currently required");
// Generate `heap_addr` instructions that are friendly to CSE by checking offsets that are
// multiples of the guard size. Add one to make sure that we check the pointer itself is in
// bounds.
//
// For accesses on the outer skirts of the guard pages, we expect that we get a trap
// even if the access goes beyond the guard pages. This is because the first byte pointed to is
// inside the guard pages.
let check_size = min(
u32::max_value() as i64,
1 + (offset as i64 / guard_size) * guard_size,
) as u32;
let base = builder.ins().heap_addr(addr_ty, heap, addr32, check_size);
// Native load/store instructions take a signed `Offset32` immediate, so adjust the base
// pointer if necessary.
if offset > i32::max_value() as u32 {
// Offset doesn't fit in the load/store instruction.
let adj = builder.ins().iadd_imm(base, i32::max_value() as i64 + 1);
(adj, (offset - (i32::max_value() as u32 + 1)) as i32)
} else {
(base, offset as i32)
}
}
// Translate a load instruction.
fn translate_load<FE: FuncEnvironment + ?Sized>(
offset: u32,
opcode: ir::Opcode,
result_ty: ir::Type,
builder: &mut FunctionBuilder<Local>,
state: &mut TranslationState,
environ: &FE,
) {
let addr32 = state.pop1();
// We don't yet support multiple linear memories.
let heap = state.get_heap(builder.func, 0, environ);
let (base, offset) = get_heap_addr(heap, addr32, offset, environ.native_pointer(), builder);
let flags = MemFlags::new();
let (load, dfg) = builder.ins().Load(
opcode,
result_ty,
flags,
offset.into(),
base,
);
state.push1(dfg.first_result(load));
}
// Translate a store instruction.
fn translate_store<FE: FuncEnvironment + ?Sized>(
offset: u32,
opcode: ir::Opcode,
builder: &mut FunctionBuilder<Local>,
state: &mut TranslationState,
environ: &FE,
) {
let (addr32, val) = state.pop2();
let val_ty = builder.func.dfg.value_type(val);
// We don't yet support multiple linear memories.
let heap = state.get_heap(builder.func, 0, environ);
let (base, offset) = get_heap_addr(heap, addr32, offset, environ.native_pointer(), builder);
let flags = MemFlags::new();
builder.ins().Store(
opcode,
val_ty,
flags,
offset.into(),
val,
base,
);
}
fn args_count(
index: FunctionIndex,
functions: &[SignatureIndex],