use crate::module::{MemoryPlan, MemoryStyle, Module, TableStyle};
use crate::vmoffsets::VMOffsets;
use crate::WASM_PAGE_SIZE;
use cranelift_codegen::cursor::FuncCursor;
use cranelift_codegen::ir;
use cranelift_codegen::ir::condcodes::*;
use cranelift_codegen::ir::immediates::{Offset32, Uimm64};
use cranelift_codegen::ir::types::*;
use cranelift_codegen::ir::{AbiParam, ArgumentPurpose, Function, InstBuilder, Signature};
use cranelift_codegen::isa::TargetFrontendConfig;
use cranelift_entity::EntityRef;
use cranelift_wasm::{
self, FuncIndex, GlobalIndex, GlobalVariable, MemoryIndex, SignatureIndex, TableIndex,
TargetEnvironment, WasmError, WasmResult,
};
#[cfg(feature = "lightbeam")]
use cranelift_wasm::{DefinedFuncIndex, DefinedGlobalIndex, DefinedMemoryIndex, DefinedTableIndex};
use std::convert::TryFrom;
pub fn get_func_name(func_index: FuncIndex) -> ir::ExternalName {
ir::ExternalName::user(0, func_index.as_u32())
}
pub fn get_memory32_grow_name() -> ir::ExternalName {
ir::ExternalName::user(1, 0)
}
pub fn get_imported_memory32_grow_name() -> ir::ExternalName {
ir::ExternalName::user(1, 1)
}
pub fn get_memory32_size_name() -> ir::ExternalName {
ir::ExternalName::user(1, 2)
}
pub fn get_imported_memory32_size_name() -> ir::ExternalName {
ir::ExternalName::user(1, 3)
}
pub struct BuiltinFunctionIndex(u32);
impl BuiltinFunctionIndex {
pub const fn get_memory32_grow_index() -> Self {
Self(0)
}
pub const fn get_imported_memory32_grow_index() -> Self {
Self(1)
}
pub const fn get_memory32_size_index() -> Self {
Self(2)
}
pub const fn get_imported_memory32_size_index() -> Self {
Self(3)
}
pub const fn builtin_functions_total_number() -> u32 {
4
}
pub const fn index(&self) -> u32 {
self.0
}
}
pub struct FuncEnvironment<'module_environment> {
target_config: TargetFrontendConfig,
module: &'module_environment Module,
vmctx: Option<ir::GlobalValue>,
memory32_size_sig: Option<ir::SigRef>,
memory_grow_sig: Option<ir::SigRef>,
offsets: VMOffsets,
}
impl<'module_environment> FuncEnvironment<'module_environment> {
pub fn new(target_config: TargetFrontendConfig, module: &'module_environment Module) -> Self {
Self {
target_config,
module,
vmctx: None,
memory32_size_sig: None,
memory_grow_sig: None,
offsets: VMOffsets::new(target_config.pointer_bytes(), module),
}
}
fn pointer_type(&self) -> ir::Type {
self.target_config.pointer_type()
}
fn vmctx(&mut self, func: &mut Function) -> ir::GlobalValue {
self.vmctx.unwrap_or_else(|| {
let vmctx = func.create_global_value(ir::GlobalValueData::VMContext);
self.vmctx = Some(vmctx);
vmctx
})
}
fn get_memory_grow_sig(&mut self, func: &mut Function) -> ir::SigRef {
let sig = self.memory_grow_sig.unwrap_or_else(|| {
func.import_signature(Signature {
params: vec![
AbiParam::special(self.pointer_type(), ArgumentPurpose::VMContext),
AbiParam::new(I32),
AbiParam::new(I32),
],
returns: vec![AbiParam::new(I32)],
call_conv: self.target_config.default_call_conv,
})
});
self.memory_grow_sig = Some(sig);
sig
}
fn get_memory_grow_func(
&mut self,
func: &mut Function,
index: MemoryIndex,
) -> (ir::SigRef, usize, BuiltinFunctionIndex) {
if self.module.is_imported_memory(index) {
(
self.get_memory_grow_sig(func),
index.index(),
BuiltinFunctionIndex::get_imported_memory32_grow_index(),
)
} else {
(
self.get_memory_grow_sig(func),
self.module.defined_memory_index(index).unwrap().index(),
BuiltinFunctionIndex::get_memory32_grow_index(),
)
}
}
fn get_memory32_size_sig(&mut self, func: &mut Function) -> ir::SigRef {
let sig = self.memory32_size_sig.unwrap_or_else(|| {
func.import_signature(Signature {
params: vec![
AbiParam::special(self.pointer_type(), ArgumentPurpose::VMContext),
AbiParam::new(I32),
],
returns: vec![AbiParam::new(I32)],
call_conv: self.target_config.default_call_conv,
})
});
self.memory32_size_sig = Some(sig);
sig
}
fn get_memory_size_func(
&mut self,
func: &mut Function,
index: MemoryIndex,
) -> (ir::SigRef, usize, BuiltinFunctionIndex) {
if self.module.is_imported_memory(index) {
(
self.get_memory32_size_sig(func),
index.index(),
BuiltinFunctionIndex::get_imported_memory32_size_index(),
)
} else {
(
self.get_memory32_size_sig(func),
self.module.defined_memory_index(index).unwrap().index(),
BuiltinFunctionIndex::get_memory32_size_index(),
)
}
}
fn translate_load_builtin_function_address(
&mut self,
pos: &mut FuncCursor<'_>,
callee_func_idx: BuiltinFunctionIndex,
) -> (ir::Value, ir::Value) {
let pointer_type = self.pointer_type();
let vmctx = self.vmctx(&mut pos.func);
let base = pos.ins().global_value(pointer_type, vmctx);
let mut mem_flags = ir::MemFlags::trusted();
mem_flags.set_readonly();
let body_offset =
i32::try_from(self.offsets.vmctx_builtin_function(callee_func_idx)).unwrap();
let func_addr = pos.ins().load(pointer_type, mem_flags, base, body_offset);
(base, func_addr)
}
}
#[cfg(feature = "lightbeam")]
impl lightbeam::ModuleContext for FuncEnvironment<'_> {
type Signature = ir::Signature;
type GlobalType = ir::Type;
fn func_index(&self, defined_func_index: u32) -> u32 {
self.module
.func_index(DefinedFuncIndex::from_u32(defined_func_index))
.as_u32()
}
fn defined_func_index(&self, func_index: u32) -> Option<u32> {
self.module
.defined_func_index(FuncIndex::from_u32(func_index))
.map(DefinedFuncIndex::as_u32)
}
fn defined_global_index(&self, global_index: u32) -> Option<u32> {
self.module
.defined_global_index(GlobalIndex::from_u32(global_index))
.map(DefinedGlobalIndex::as_u32)
}
fn global_type(&self, global_index: u32) -> &Self::GlobalType {
&self.module.globals[GlobalIndex::from_u32(global_index)].ty
}
fn func_type_index(&self, func_idx: u32) -> u32 {
self.module.functions[FuncIndex::from_u32(func_idx)].as_u32()
}
fn signature(&self, index: u32) -> &Self::Signature {
&self.module.signatures[SignatureIndex::from_u32(index)]
}
fn defined_table_index(&self, table_index: u32) -> Option<u32> {
self.module
.defined_table_index(TableIndex::from_u32(table_index))
.map(DefinedTableIndex::as_u32)
}
fn defined_memory_index(&self, memory_index: u32) -> Option<u32> {
self.module
.defined_memory_index(MemoryIndex::from_u32(memory_index))
.map(DefinedMemoryIndex::as_u32)
}
fn vmctx_vmfunction_import_body(&self, func_index: u32) -> u32 {
self.offsets
.vmctx_vmfunction_import_body(FuncIndex::from_u32(func_index))
}
fn vmctx_vmfunction_import_vmctx(&self, func_index: u32) -> u32 {
self.offsets
.vmctx_vmfunction_import_vmctx(FuncIndex::from_u32(func_index))
}
fn vmctx_vmglobal_import_from(&self, global_index: u32) -> u32 {
self.offsets
.vmctx_vmglobal_import_from(GlobalIndex::from_u32(global_index))
}
fn vmctx_vmglobal_definition(&self, defined_global_index: u32) -> u32 {
self.offsets
.vmctx_vmglobal_definition(DefinedGlobalIndex::from_u32(defined_global_index))
}
fn vmctx_vmmemory_import_from(&self, memory_index: u32) -> u32 {
self.offsets
.vmctx_vmmemory_import_from(MemoryIndex::from_u32(memory_index))
}
fn vmctx_vmmemory_definition(&self, defined_memory_index: u32) -> u32 {
self.offsets
.vmctx_vmmemory_definition(DefinedMemoryIndex::from_u32(defined_memory_index))
}
fn vmctx_vmmemory_definition_base(&self, defined_memory_index: u32) -> u32 {
self.offsets
.vmctx_vmmemory_definition_base(DefinedMemoryIndex::from_u32(defined_memory_index))
}
fn vmctx_vmmemory_definition_current_length(&self, defined_memory_index: u32) -> u32 {
self.offsets
.vmctx_vmmemory_definition_current_length(DefinedMemoryIndex::from_u32(
defined_memory_index,
))
}
fn vmmemory_definition_base(&self) -> u8 {
self.offsets.vmmemory_definition_base()
}
fn vmmemory_definition_current_length(&self) -> u8 {
self.offsets.vmmemory_definition_current_length()
}
fn vmctx_vmtable_import_from(&self, table_index: u32) -> u32 {
self.offsets
.vmctx_vmtable_import_from(TableIndex::from_u32(table_index))
}
fn vmctx_vmtable_definition(&self, defined_table_index: u32) -> u32 {
self.offsets
.vmctx_vmtable_definition(DefinedTableIndex::from_u32(defined_table_index))
}
fn vmctx_vmtable_definition_base(&self, defined_table_index: u32) -> u32 {
self.offsets
.vmctx_vmtable_definition_base(DefinedTableIndex::from_u32(defined_table_index))
}
fn vmctx_vmtable_definition_current_elements(&self, defined_table_index: u32) -> u32 {
self.offsets
.vmctx_vmtable_definition_current_elements(DefinedTableIndex::from_u32(
defined_table_index,
))
}
fn vmtable_definition_base(&self) -> u8 {
self.offsets.vmtable_definition_base()
}
fn vmtable_definition_current_elements(&self) -> u8 {
self.offsets.vmtable_definition_current_elements()
}
fn vmcaller_checked_anyfunc_type_index(&self) -> u8 {
self.offsets.vmcaller_checked_anyfunc_type_index()
}
fn vmcaller_checked_anyfunc_func_ptr(&self) -> u8 {
self.offsets.vmcaller_checked_anyfunc_func_ptr()
}
fn vmcaller_checked_anyfunc_vmctx(&self) -> u8 {
self.offsets.vmcaller_checked_anyfunc_vmctx()
}
fn size_of_vmcaller_checked_anyfunc(&self) -> u8 {
self.offsets.size_of_vmcaller_checked_anyfunc()
}
fn vmctx_vmshared_signature_id(&self, signature_idx: u32) -> u32 {
self.offsets
.vmctx_vmshared_signature_id(SignatureIndex::from_u32(signature_idx))
}
}
impl<'module_environment> TargetEnvironment for FuncEnvironment<'module_environment> {
fn target_config(&self) -> TargetFrontendConfig {
self.target_config
}
}
impl<'module_environment> cranelift_wasm::FuncEnvironment for FuncEnvironment<'module_environment> {
fn make_table(&mut self, func: &mut ir::Function, index: TableIndex) -> WasmResult<ir::Table> {
let pointer_type = self.pointer_type();
let (ptr, base_offset, current_elements_offset) = {
let vmctx = self.vmctx(func);
if let Some(def_index) = self.module.defined_table_index(index) {
let base_offset =
i32::try_from(self.offsets.vmctx_vmtable_definition_base(def_index)).unwrap();
let current_elements_offset = i32::try_from(
self.offsets
.vmctx_vmtable_definition_current_elements(def_index),
)
.unwrap();
(vmctx, base_offset, current_elements_offset)
} else {
let from_offset = self.offsets.vmctx_vmtable_import_from(index);
let table = func.create_global_value(ir::GlobalValueData::Load {
base: vmctx,
offset: Offset32::new(i32::try_from(from_offset).unwrap()),
global_type: pointer_type,
readonly: true,
});
let base_offset = i32::from(self.offsets.vmtable_definition_base());
let current_elements_offset =
i32::from(self.offsets.vmtable_definition_current_elements());
(table, base_offset, current_elements_offset)
}
};
let base_gv = func.create_global_value(ir::GlobalValueData::Load {
base: ptr,
offset: Offset32::new(base_offset),
global_type: pointer_type,
readonly: false,
});
let bound_gv = func.create_global_value(ir::GlobalValueData::Load {
base: ptr,
offset: Offset32::new(current_elements_offset),
global_type: self.offsets.type_of_vmtable_definition_current_elements(),
readonly: false,
});
let element_size = match self.module.table_plans[index].style {
TableStyle::CallerChecksSignature => {
u64::from(self.offsets.size_of_vmcaller_checked_anyfunc())
}
};
Ok(func.create_table(ir::TableData {
base_gv,
min_size: Uimm64::new(0),
bound_gv,
element_size: Uimm64::new(element_size),
index_type: I32,
}))
}
fn make_heap(&mut self, func: &mut ir::Function, index: MemoryIndex) -> WasmResult<ir::Heap> {
let pointer_type = self.pointer_type();
let (ptr, base_offset, current_length_offset) = {
let vmctx = self.vmctx(func);
if let Some(def_index) = self.module.defined_memory_index(index) {
let base_offset =
i32::try_from(self.offsets.vmctx_vmmemory_definition_base(def_index)).unwrap();
let current_length_offset = i32::try_from(
self.offsets
.vmctx_vmmemory_definition_current_length(def_index),
)
.unwrap();
(vmctx, base_offset, current_length_offset)
} else {
let from_offset = self.offsets.vmctx_vmmemory_import_from(index);
let memory = func.create_global_value(ir::GlobalValueData::Load {
base: vmctx,
offset: Offset32::new(i32::try_from(from_offset).unwrap()),
global_type: pointer_type,
readonly: true,
});
let base_offset = i32::from(self.offsets.vmmemory_definition_base());
let current_length_offset =
i32::from(self.offsets.vmmemory_definition_current_length());
(memory, base_offset, current_length_offset)
}
};
let (offset_guard_size, heap_style, readonly_base) = match self.module.memory_plans[index] {
MemoryPlan {
style: MemoryStyle::Dynamic,
offset_guard_size,
memory: _,
} => {
let heap_bound = func.create_global_value(ir::GlobalValueData::Load {
base: ptr,
offset: Offset32::new(current_length_offset),
global_type: self.offsets.type_of_vmmemory_definition_current_length(),
readonly: false,
});
(
Uimm64::new(offset_guard_size),
ir::HeapStyle::Dynamic {
bound_gv: heap_bound,
},
false,
)
}
MemoryPlan {
style: MemoryStyle::Static { bound },
offset_guard_size,
memory: _,
} => (
Uimm64::new(offset_guard_size),
ir::HeapStyle::Static {
bound: Uimm64::new(u64::from(bound) * u64::from(WASM_PAGE_SIZE)),
},
true,
),
};
let heap_base = func.create_global_value(ir::GlobalValueData::Load {
base: ptr,
offset: Offset32::new(base_offset),
global_type: pointer_type,
readonly: readonly_base,
});
Ok(func.create_heap(ir::HeapData {
base: heap_base,
min_size: 0.into(),
offset_guard_size,
style: heap_style,
index_type: I32,
}))
}
fn make_global(
&mut self,
func: &mut ir::Function,
index: GlobalIndex,
) -> WasmResult<GlobalVariable> {
let pointer_type = self.pointer_type();
let (ptr, offset) = {
let vmctx = self.vmctx(func);
if let Some(def_index) = self.module.defined_global_index(index) {
let offset =
i32::try_from(self.offsets.vmctx_vmglobal_definition(def_index)).unwrap();
(vmctx, offset)
} else {
let from_offset = self.offsets.vmctx_vmglobal_import_from(index);
let global = func.create_global_value(ir::GlobalValueData::Load {
base: vmctx,
offset: Offset32::new(i32::try_from(from_offset).unwrap()),
global_type: pointer_type,
readonly: true,
});
(global, 0)
}
};
Ok(GlobalVariable::Memory {
gv: ptr,
offset: offset.into(),
ty: self.module.globals[index].ty,
})
}
fn make_indirect_sig(
&mut self,
func: &mut ir::Function,
index: SignatureIndex,
) -> WasmResult<ir::SigRef> {
Ok(func.import_signature(self.module.signatures[index].clone()))
}
fn make_direct_func(
&mut self,
func: &mut ir::Function,
index: FuncIndex,
) -> WasmResult<ir::FuncRef> {
let sigidx = self.module.functions[index];
let signature = func.import_signature(self.module.signatures[sigidx].clone());
let name = get_func_name(index);
Ok(func.import_function(ir::ExtFuncData {
name,
signature,
colocated: false,
}))
}
fn translate_call_indirect(
&mut self,
mut pos: FuncCursor<'_>,
table_index: TableIndex,
table: ir::Table,
sig_index: SignatureIndex,
sig_ref: ir::SigRef,
callee: ir::Value,
call_args: &[ir::Value],
) -> WasmResult<ir::Inst> {
let pointer_type = self.pointer_type();
let table_entry_addr = pos.ins().table_addr(pointer_type, table, callee, 0);
let mem_flags = ir::MemFlags::trusted();
let func_addr = pos.ins().load(
pointer_type,
mem_flags,
table_entry_addr,
i32::from(self.offsets.vmcaller_checked_anyfunc_func_ptr()),
);
pos.ins().trapz(func_addr, ir::TrapCode::IndirectCallToNull);
match self.module.table_plans[table_index].style {
TableStyle::CallerChecksSignature => {
let sig_id_size = self.offsets.size_of_vmshared_signature_index();
let sig_id_type = Type::int(u16::from(sig_id_size) * 8).unwrap();
let vmctx = self.vmctx(pos.func);
let base = pos.ins().global_value(pointer_type, vmctx);
let offset =
i32::try_from(self.offsets.vmctx_vmshared_signature_id(sig_index)).unwrap();
let mut mem_flags = ir::MemFlags::trusted();
mem_flags.set_readonly();
let caller_sig_id = pos.ins().load(sig_id_type, mem_flags, base, offset);
let mem_flags = ir::MemFlags::trusted();
let callee_sig_id = pos.ins().load(
sig_id_type,
mem_flags,
table_entry_addr,
i32::from(self.offsets.vmcaller_checked_anyfunc_type_index()),
);
let cmp = pos.ins().icmp(IntCC::Equal, callee_sig_id, caller_sig_id);
pos.ins().trapz(cmp, ir::TrapCode::BadSignature);
}
}
let mut real_call_args = Vec::with_capacity(call_args.len() + 1);
let vmctx = pos.ins().load(
pointer_type,
mem_flags,
table_entry_addr,
i32::from(self.offsets.vmcaller_checked_anyfunc_vmctx()),
);
real_call_args.push(vmctx);
real_call_args.extend_from_slice(call_args);
Ok(pos.ins().call_indirect(sig_ref, func_addr, &real_call_args))
}
fn translate_call(
&mut self,
mut pos: FuncCursor<'_>,
callee_index: FuncIndex,
callee: ir::FuncRef,
call_args: &[ir::Value],
) -> WasmResult<ir::Inst> {
let mut real_call_args = Vec::with_capacity(call_args.len() + 1);
if !self.module.is_imported_function(callee_index) {
real_call_args.push(pos.func.special_param(ArgumentPurpose::VMContext).unwrap());
real_call_args.extend_from_slice(call_args);
return Ok(pos.ins().call(callee, &real_call_args));
}
let pointer_type = self.pointer_type();
let sig_ref = pos.func.dfg.ext_funcs[callee].signature;
let vmctx = self.vmctx(&mut pos.func);
let base = pos.ins().global_value(pointer_type, vmctx);
let mem_flags = ir::MemFlags::trusted();
let body_offset =
i32::try_from(self.offsets.vmctx_vmfunction_import_body(callee_index)).unwrap();
let func_addr = pos.ins().load(pointer_type, mem_flags, base, body_offset);
let vmctx_offset =
i32::try_from(self.offsets.vmctx_vmfunction_import_vmctx(callee_index)).unwrap();
let vmctx = pos.ins().load(pointer_type, mem_flags, base, vmctx_offset);
real_call_args.push(vmctx);
real_call_args.extend_from_slice(call_args);
Ok(pos.ins().call_indirect(sig_ref, func_addr, &real_call_args))
}
fn translate_memory_grow(
&mut self,
mut pos: FuncCursor<'_>,
index: MemoryIndex,
_heap: ir::Heap,
val: ir::Value,
) -> WasmResult<ir::Value> {
let (func_sig, index_arg, func_idx) = self.get_memory_grow_func(&mut pos.func, index);
let memory_index = pos.ins().iconst(I32, index_arg as i64);
let (vmctx, func_addr) = self.translate_load_builtin_function_address(&mut pos, func_idx);
let call_inst = pos
.ins()
.call_indirect(func_sig, func_addr, &[vmctx, val, memory_index]);
Ok(*pos.func.dfg.inst_results(call_inst).first().unwrap())
}
fn translate_memory_size(
&mut self,
mut pos: FuncCursor<'_>,
index: MemoryIndex,
_heap: ir::Heap,
) -> WasmResult<ir::Value> {
let (func_sig, index_arg, func_idx) = self.get_memory_size_func(&mut pos.func, index);
let memory_index = pos.ins().iconst(I32, index_arg as i64);
let (vmctx, func_addr) = self.translate_load_builtin_function_address(&mut pos, func_idx);
let call_inst = pos
.ins()
.call_indirect(func_sig, func_addr, &[vmctx, memory_index]);
Ok(*pos.func.dfg.inst_results(call_inst).first().unwrap())
}
fn translate_memory_copy(
&mut self,
_pos: FuncCursor,
_index: MemoryIndex,
_heap: ir::Heap,
_dst: ir::Value,
_src: ir::Value,
_len: ir::Value,
) -> WasmResult<()> {
Err(WasmError::Unsupported("bulk memory".to_string()))
}
fn translate_memory_fill(
&mut self,
_pos: FuncCursor,
_index: MemoryIndex,
_heap: ir::Heap,
_dst: ir::Value,
_val: ir::Value,
_len: ir::Value,
) -> WasmResult<()> {
Err(WasmError::Unsupported("bulk memory".to_string()))
}
fn translate_memory_init(
&mut self,
_pos: FuncCursor,
_index: MemoryIndex,
_heap: ir::Heap,
_seg_index: u32,
_dst: ir::Value,
_src: ir::Value,
_len: ir::Value,
) -> WasmResult<()> {
Err(WasmError::Unsupported("bulk memory".to_string()))
}
fn translate_data_drop(&mut self, _pos: FuncCursor, _seg_index: u32) -> WasmResult<()> {
Err(WasmError::Unsupported("bulk memory".to_string()))
}
fn translate_table_size(
&mut self,
_pos: FuncCursor,
_index: TableIndex,
_table: ir::Table,
) -> WasmResult<ir::Value> {
Err(WasmError::Unsupported("bulk memory".to_string()))
}
fn translate_table_copy(
&mut self,
_pos: FuncCursor,
_dst_table_index: TableIndex,
_dst_table: ir::Table,
_src_table_index: TableIndex,
_src_table: ir::Table,
_dst: ir::Value,
_src: ir::Value,
_len: ir::Value,
) -> WasmResult<()> {
Err(WasmError::Unsupported("bulk memory".to_string()))
}
fn translate_table_init(
&mut self,
_pos: FuncCursor,
_seg_index: u32,
_table_index: TableIndex,
_table: ir::Table,
_dst: ir::Value,
_src: ir::Value,
_len: ir::Value,
) -> WasmResult<()> {
Err(WasmError::Unsupported("bulk memory".to_string()))
}
fn translate_elem_drop(&mut self, _pos: FuncCursor, _seg_index: u32) -> WasmResult<()> {
Err(WasmError::Unsupported("bulk memory".to_string()))
}
}