106f96b066
This shows how to define, export and import functions written in Go. Fixes #464 Signed-off-by: Adrian Cole <adrian@tetrate.io> Co-authored-by: Takeshi Yoneda <takeshi@tetrate.io>
1171 lines
41 KiB
Go
1171 lines
41 KiB
Go
package wasm
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import (
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"bytes"
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"errors"
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"fmt"
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"strconv"
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"strings"
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"github.com/tetratelabs/wazero/api"
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"github.com/tetratelabs/wazero/internal/leb128"
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)
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// The wazero specific limitation described at RATIONALE.md.
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const maximumValuesOnStack = 1 << 27
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// validateFunction validates the instruction sequence of a function.
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// following the specification https://www.w3.org/TR/2019/REC-wasm-core-1-20191205/#instructions%E2%91%A2.
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//
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// * idx is the index in the FunctionSection
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// * functions are the function index namespace, which is prefixed by imports. The value is the TypeSection index.
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// * globals are the global index namespace, which is prefixed by imports.
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// * memory is the potentially imported memory and can be nil.
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// * table is the potentially imported table and can be nil.
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//
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// Returns an error if the instruction sequence is not valid,
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// or potentially it can exceed the maximum number of values on the stack.
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func (m *Module) validateFunction(enabledFeatures Features, idx Index, functions []Index, globals []*GlobalType, memory *Memory, table *Table) error {
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return m.validateFunctionWithMaxStackValues(enabledFeatures, idx, functions, globals, memory, table, maximumValuesOnStack)
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}
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// validateFunctionWithMaxStackValues is like validateFunction, but allows overriding maxStackValues for testing.
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//
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// * maxStackValues is the maximum height of values stack which the target is allowed to reach.
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func (m *Module) validateFunctionWithMaxStackValues(
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enabledFeatures Features,
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idx Index,
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functions []Index,
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globals []*GlobalType,
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memory *Memory,
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table *Table,
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maxStackValues int,
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) error {
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functionType := m.TypeSection[m.FunctionSection[idx]]
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body := m.CodeSection[idx].Body
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localTypes := m.CodeSection[idx].LocalTypes
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types := m.TypeSection
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// We start with the outermost control block which is for function return if the code branches into it.
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controlBlockStack := []*controlBlock{{blockType: functionType}}
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// Create the valueTypeStack to track the state of Wasm value stacks at anypoint of execution.
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valueTypeStack := &valueTypeStack{}
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// Now start walking through all the instructions in the body while tracking
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// control blocks and value types to check the validity of all instructions.
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for pc := uint64(0); pc < uint64(len(body)); pc++ {
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op := body[pc]
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if OpcodeI32Load <= op && op <= OpcodeI64Store32 {
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if memory == nil {
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return fmt.Errorf("unknown memory access")
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}
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pc++
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align, num, err := leb128.DecodeUint32(bytes.NewReader(body[pc:]))
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if err != nil {
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return fmt.Errorf("read memory align: %v", err)
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}
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switch op {
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case OpcodeI32Load:
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if 1<<align > 32/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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valueTypeStack.push(ValueTypeI32)
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case OpcodeF32Load:
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if 1<<align > 32/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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valueTypeStack.push(ValueTypeF32)
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case OpcodeI32Store:
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if 1<<align > 32/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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case OpcodeF32Store:
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if 1<<align > 32/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeF32); err != nil {
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return err
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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case OpcodeI64Load:
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if 1<<align > 64/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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valueTypeStack.push(ValueTypeI64)
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case OpcodeF64Load:
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if 1<<align > 64/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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valueTypeStack.push(ValueTypeF64)
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case OpcodeI64Store:
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if 1<<align > 64/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
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return err
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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case OpcodeF64Store:
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if 1<<align > 64/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeF64); err != nil {
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return err
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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case OpcodeI32Load8S:
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if 1<<align > 1 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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valueTypeStack.push(ValueTypeI32)
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case OpcodeI32Load8U:
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if 1<<align > 1 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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valueTypeStack.push(ValueTypeI32)
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case OpcodeI64Load8S, OpcodeI64Load8U:
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if 1<<align > 1 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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valueTypeStack.push(ValueTypeI64)
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case OpcodeI32Store8:
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if 1<<align > 1 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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case OpcodeI64Store8:
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if 1<<align > 1 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
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return err
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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case OpcodeI32Load16S, OpcodeI32Load16U:
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if 1<<align > 16/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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valueTypeStack.push(ValueTypeI32)
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case OpcodeI64Load16S, OpcodeI64Load16U:
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if 1<<align > 16/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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valueTypeStack.push(ValueTypeI64)
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case OpcodeI32Store16:
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if 1<<align > 16/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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case OpcodeI64Store16:
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if 1<<align > 16/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
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return err
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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case OpcodeI64Load32S, OpcodeI64Load32U:
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if 1<<align > 32/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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valueTypeStack.push(ValueTypeI64)
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case OpcodeI64Store32:
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if 1<<align > 32/8 {
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return fmt.Errorf("invalid memory alignment")
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
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return err
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}
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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}
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pc += num
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// offset
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_, num, err = leb128.DecodeUint32(bytes.NewReader(body[pc:]))
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if err != nil {
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return fmt.Errorf("read memory offset: %v", err)
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}
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pc += num - 1
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} else if OpcodeMemorySize <= op && op <= OpcodeMemoryGrow {
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if memory == nil {
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return fmt.Errorf("unknown memory access")
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}
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pc++
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val, num, err := leb128.DecodeUint32(bytes.NewReader(body[pc:]))
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if err != nil {
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return fmt.Errorf("read immediate: %v", err)
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}
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if val != 0 || num != 1 {
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return fmt.Errorf("memory instruction reserved bytes not zero with 1 byte")
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}
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switch Opcode(op) {
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case OpcodeMemoryGrow:
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return err
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}
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valueTypeStack.push(ValueTypeI32)
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case OpcodeMemorySize:
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valueTypeStack.push(ValueTypeI32)
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}
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pc += num - 1
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} else if OpcodeI32Const <= op && op <= OpcodeF64Const {
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pc++
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switch Opcode(op) {
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case OpcodeI32Const:
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_, num, err := leb128.DecodeInt32(bytes.NewReader(body[pc:]))
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if err != nil {
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return fmt.Errorf("read i32 immediate: %s", err)
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}
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pc += num - 1
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valueTypeStack.push(ValueTypeI32)
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case OpcodeI64Const:
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_, num, err := leb128.DecodeInt64(bytes.NewReader(body[pc:]))
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if err != nil {
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return fmt.Errorf("read i64 immediate: %v", err)
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}
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valueTypeStack.push(ValueTypeI64)
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pc += num - 1
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case OpcodeF32Const:
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valueTypeStack.push(ValueTypeF32)
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pc += 3
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case OpcodeF64Const:
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valueTypeStack.push(ValueTypeF64)
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pc += 7
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}
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} else if OpcodeLocalGet <= op && op <= OpcodeGlobalSet {
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pc++
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index, num, err := leb128.DecodeUint32(bytes.NewReader(body[pc:]))
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if err != nil {
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return fmt.Errorf("read immediate: %v", err)
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}
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pc += num - 1
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switch op {
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case OpcodeLocalGet:
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inputLen := uint32(len(functionType.Params))
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if l := uint32(len(localTypes)) + inputLen; index >= l {
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return fmt.Errorf("invalid local index for %s %d >= %d(=len(locals)+len(parameters))",
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OpcodeLocalGetName, index, l)
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}
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if index < inputLen {
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valueTypeStack.push(functionType.Params[index])
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} else {
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valueTypeStack.push(localTypes[index-inputLen])
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}
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case OpcodeLocalSet:
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inputLen := uint32(len(functionType.Params))
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if l := uint32(len(localTypes)) + inputLen; index >= l {
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return fmt.Errorf("invalid local index for %s %d >= %d(=len(locals)+len(parameters))",
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OpcodeLocalSetName, index, l)
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}
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var expType ValueType
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if index < inputLen {
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expType = functionType.Params[index]
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} else {
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expType = localTypes[index-inputLen]
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}
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if err := valueTypeStack.popAndVerifyType(expType); err != nil {
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return err
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}
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case OpcodeLocalTee:
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inputLen := uint32(len(functionType.Params))
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if l := uint32(len(localTypes)) + inputLen; index >= l {
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return fmt.Errorf("invalid local index for %s %d >= %d(=len(locals)+len(parameters))",
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OpcodeLocalTeeName, index, l)
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}
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var expType ValueType
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if index < inputLen {
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expType = functionType.Params[index]
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} else {
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expType = localTypes[index-inputLen]
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}
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if err := valueTypeStack.popAndVerifyType(expType); err != nil {
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return err
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}
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valueTypeStack.push(expType)
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case OpcodeGlobalGet:
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if index >= uint32(len(globals)) {
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return fmt.Errorf("invalid index for %s", OpcodeGlobalGetName)
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}
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valueTypeStack.push(globals[index].ValType)
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case OpcodeGlobalSet:
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if index >= uint32(len(globals)) {
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return fmt.Errorf("invalid global index")
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} else if !globals[index].Mutable {
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return fmt.Errorf("%s when not mutable", OpcodeGlobalSetName)
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} else if err := valueTypeStack.popAndVerifyType(
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globals[index].ValType); err != nil {
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return err
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}
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}
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} else if op == OpcodeBr {
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pc++
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index, num, err := leb128.DecodeUint32(bytes.NewReader(body[pc:]))
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if err != nil {
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return fmt.Errorf("read immediate: %v", err)
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} else if int(index) >= len(controlBlockStack) {
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return fmt.Errorf("invalid %s operation: index out of range", OpcodeBrName)
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}
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pc += num - 1
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// Check type soundness.
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target := controlBlockStack[len(controlBlockStack)-int(index)-1]
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targetResultType := target.blockType.Results
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if target.op == OpcodeLoop {
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// Loop operation doesn't require results since the continuation is
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// the beginning of the loop.
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targetResultType = []ValueType{}
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}
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if err = valueTypeStack.popResults(op, targetResultType, false); err != nil {
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return err
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}
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// br instruction is stack-polymorphic.
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valueTypeStack.unreachable()
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} else if op == OpcodeBrIf {
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pc++
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index, num, err := leb128.DecodeUint32(bytes.NewReader(body[pc:]))
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if err != nil {
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return fmt.Errorf("read immediate: %v", err)
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} else if int(index) >= len(controlBlockStack) {
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return fmt.Errorf(
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"invalid ln param given for %s: index=%d with %d for the current lable stack length",
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OpcodeBrIfName, index, len(controlBlockStack))
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}
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pc += num - 1
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return fmt.Errorf("cannot pop the required operand for %s", OpcodeBrIfName)
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}
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// Check type soundness.
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target := controlBlockStack[len(controlBlockStack)-int(index)-1]
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targetResultType := target.blockType.Results
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if target.op == OpcodeLoop {
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// Loop operation doesn't require results since the continuation is
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// the beginning of the loop.
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targetResultType = []ValueType{}
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}
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if err := valueTypeStack.popResults(op, targetResultType, false); err != nil {
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return err
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}
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// Push back the result
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for _, t := range targetResultType {
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valueTypeStack.push(t)
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}
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} else if op == OpcodeBrTable {
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pc++
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r := bytes.NewReader(body[pc:])
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nl, num, err := leb128.DecodeUint32(r)
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if err != nil {
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return fmt.Errorf("read immediate: %w", err)
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}
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list := make([]uint32, nl)
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for i := uint32(0); i < nl; i++ {
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l, n, err := leb128.DecodeUint32(r)
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if err != nil {
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return fmt.Errorf("read immediate: %w", err)
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}
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num += n
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list[i] = l
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}
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ln, n, err := leb128.DecodeUint32(r)
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if err != nil {
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return fmt.Errorf("read immediate: %w", err)
|
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} else if int(ln) >= len(controlBlockStack) {
|
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return fmt.Errorf(
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"invalid ln param given for %s: ln=%d with %d for the current lable stack length",
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OpcodeBrTableName, ln, len(controlBlockStack))
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}
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pc += n + num - 1
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// Check type soundness.
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if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
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return fmt.Errorf("cannot pop the required operand for %s", OpcodeBrTableName)
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}
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lnLabel := controlBlockStack[len(controlBlockStack)-1-int(ln)]
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expType := lnLabel.blockType.Results
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if lnLabel.op == OpcodeLoop {
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// Loop operation doesn't require results since the continuation is
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// the beginning of the loop.
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expType = []ValueType{}
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}
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for _, l := range list {
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if int(l) >= len(controlBlockStack) {
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return fmt.Errorf("invalid l param given for %s", OpcodeBrTableName)
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}
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label := controlBlockStack[len(controlBlockStack)-1-int(l)]
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expType2 := label.blockType.Results
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if label.op == OpcodeLoop {
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// Loop operation doesn't require results since the continuation is
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// the beginning of the loop.
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expType2 = []ValueType{}
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}
|
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if len(expType) != len(expType2) {
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return fmt.Errorf("incosistent block type length for %s at %d; %v (ln=%d) != %v (l=%d)", OpcodeBrTableName, l, expType, ln, expType2, l)
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}
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for i := range expType {
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if expType[i] != expType2[i] {
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return fmt.Errorf("incosistent block type for %s at %d", OpcodeBrTableName, l)
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}
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}
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}
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if err = valueTypeStack.popResults(op, expType, false); err != nil {
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return err
|
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}
|
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// br_table instruction is stack-polymorphic.
|
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valueTypeStack.unreachable()
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} else if op == OpcodeCall {
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pc++
|
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index, num, err := leb128.DecodeUint32(bytes.NewReader(body[pc:]))
|
|
if err != nil {
|
|
return fmt.Errorf("read immediate: %v", err)
|
|
}
|
|
pc += num - 1
|
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if int(index) >= len(functions) {
|
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return fmt.Errorf("invalid function index")
|
|
}
|
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funcType := types[functions[index]]
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for i := 0; i < len(funcType.Params); i++ {
|
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if err := valueTypeStack.popAndVerifyType(funcType.Params[len(funcType.Params)-1-i]); err != nil {
|
|
return fmt.Errorf("type mismatch on %s operation param type: %v", OpcodeCallName, err)
|
|
}
|
|
}
|
|
for _, exp := range funcType.Results {
|
|
valueTypeStack.push(exp)
|
|
}
|
|
} else if op == OpcodeCallIndirect {
|
|
pc++
|
|
typeIndex, num, err := leb128.DecodeUint32(bytes.NewReader(body[pc:]))
|
|
if err != nil {
|
|
return fmt.Errorf("read immediate: %v", err)
|
|
}
|
|
pc += num - 1
|
|
pc++
|
|
if body[pc] != 0x00 {
|
|
return fmt.Errorf("%s reserved bytes not zero but got %d", OpcodeCallIndirectName, body[pc])
|
|
}
|
|
if table == nil {
|
|
return fmt.Errorf("table not given while having %s", OpcodeCallIndirectName)
|
|
}
|
|
if err = valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the in table index's type for %s", OpcodeCallIndirectName)
|
|
}
|
|
if int(typeIndex) >= len(types) {
|
|
return fmt.Errorf("invalid type index at %s: %d", OpcodeCallIndirectName, typeIndex)
|
|
}
|
|
funcType := types[typeIndex]
|
|
for i := 0; i < len(funcType.Params); i++ {
|
|
if err = valueTypeStack.popAndVerifyType(funcType.Params[len(funcType.Params)-1-i]); err != nil {
|
|
return fmt.Errorf("type mismatch on %s operation input type", OpcodeCallIndirectName)
|
|
}
|
|
}
|
|
for _, exp := range funcType.Results {
|
|
valueTypeStack.push(exp)
|
|
}
|
|
} else if OpcodeI32Eqz <= op && op <= LastOpcode {
|
|
switch op {
|
|
case OpcodeI32Eqz:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the operand for %s: %v", OpcodeI32EqzName, err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeI32Eq, OpcodeI32Ne, OpcodeI32LtS,
|
|
OpcodeI32LtU, OpcodeI32GtS, OpcodeI32GtU, OpcodeI32LeS,
|
|
OpcodeI32LeU, OpcodeI32GeS, OpcodeI32GeU:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the 1st i32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the 2nd i32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeI64Eqz:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
|
|
return fmt.Errorf("cannot pop the operand for %s: %v", OpcodeI64EqzName, err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeI64Eq, OpcodeI64Ne, OpcodeI64LtS,
|
|
OpcodeI64LtU, OpcodeI64GtS, OpcodeI64GtU,
|
|
OpcodeI64LeS, OpcodeI64LeU, OpcodeI64GeS, OpcodeI64GeU:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
|
|
return fmt.Errorf("cannot pop the 1st i64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
|
|
return fmt.Errorf("cannot pop the 2nd i64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeF32Eq, OpcodeF32Ne, OpcodeF32Lt, OpcodeF32Gt, OpcodeF32Le, OpcodeF32Ge:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF32); err != nil {
|
|
return fmt.Errorf("cannot pop the 1st f32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF32); err != nil {
|
|
return fmt.Errorf("cannot pop the 2nd f32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeF64Eq, OpcodeF64Ne, OpcodeF64Lt, OpcodeF64Gt, OpcodeF64Le, OpcodeF64Ge:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF64); err != nil {
|
|
return fmt.Errorf("cannot pop the 1st f64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF64); err != nil {
|
|
return fmt.Errorf("cannot pop the 2nd f64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeI32Clz, OpcodeI32Ctz, OpcodeI32Popcnt:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the i32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeI32Add, OpcodeI32Sub, OpcodeI32Mul, OpcodeI32DivS,
|
|
OpcodeI32DivU, OpcodeI32RemS, OpcodeI32RemU, OpcodeI32And,
|
|
OpcodeI32Or, OpcodeI32Xor, OpcodeI32Shl, OpcodeI32ShrS,
|
|
OpcodeI32ShrU, OpcodeI32Rotl, OpcodeI32Rotr:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the 1st operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the 2nd operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeI64Clz, OpcodeI64Ctz, OpcodeI64Popcnt:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
|
|
return fmt.Errorf("cannot pop the i64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI64)
|
|
case OpcodeI64Add, OpcodeI64Sub, OpcodeI64Mul, OpcodeI64DivS,
|
|
OpcodeI64DivU, OpcodeI64RemS, OpcodeI64RemU, OpcodeI64And,
|
|
OpcodeI64Or, OpcodeI64Xor, OpcodeI64Shl, OpcodeI64ShrS,
|
|
OpcodeI64ShrU, OpcodeI64Rotl, OpcodeI64Rotr:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
|
|
return fmt.Errorf("cannot pop the 1st i64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
|
|
return fmt.Errorf("cannot pop the 2nd i64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI64)
|
|
case OpcodeF32Abs, OpcodeF32Neg, OpcodeF32Ceil,
|
|
OpcodeF32Floor, OpcodeF32Trunc, OpcodeF32Nearest,
|
|
OpcodeF32Sqrt:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF32); err != nil {
|
|
return fmt.Errorf("cannot pop the 1st f32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeF32)
|
|
case OpcodeF32Add, OpcodeF32Sub, OpcodeF32Mul,
|
|
OpcodeF32Div, OpcodeF32Min, OpcodeF32Max,
|
|
OpcodeF32Copysign:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF32); err != nil {
|
|
return fmt.Errorf("cannot pop the 1st f32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF32); err != nil {
|
|
return fmt.Errorf("cannot pop the 2nd f32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeF32)
|
|
case OpcodeF64Abs, OpcodeF64Neg, OpcodeF64Ceil,
|
|
OpcodeF64Floor, OpcodeF64Trunc, OpcodeF64Nearest,
|
|
OpcodeF64Sqrt:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF64); err != nil {
|
|
return fmt.Errorf("cannot pop the 1st f64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeF64)
|
|
case OpcodeF64Add, OpcodeF64Sub, OpcodeF64Mul,
|
|
OpcodeF64Div, OpcodeF64Min, OpcodeF64Max,
|
|
OpcodeF64Copysign:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF64); err != nil {
|
|
return fmt.Errorf("cannot pop the 1st f64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF64); err != nil {
|
|
return fmt.Errorf("cannot pop the 2nd f64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeF64)
|
|
case OpcodeI32WrapI64:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
|
|
return fmt.Errorf("cannot pop the operand for %s: %v", OpcodeI32WrapI64Name, err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeI32TruncF32S, OpcodeI32TruncF32U:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF32); err != nil {
|
|
return fmt.Errorf("cannot pop the f32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeI32TruncF64S, OpcodeI32TruncF64U:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF64); err != nil {
|
|
return fmt.Errorf("cannot pop the f64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeI64ExtendI32S, OpcodeI64ExtendI32U:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the i32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI64)
|
|
case OpcodeI64TruncF32S, OpcodeI64TruncF32U:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF32); err != nil {
|
|
return fmt.Errorf("cannot pop the f32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI64)
|
|
case OpcodeI64TruncF64S, OpcodeI64TruncF64U:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF64); err != nil {
|
|
return fmt.Errorf("cannot pop the f64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI64)
|
|
case OpcodeF32ConvertI32s, OpcodeF32ConvertI32U:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the i32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeF32)
|
|
case OpcodeF32ConvertI64S, OpcodeF32ConvertI64U:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
|
|
return fmt.Errorf("cannot pop the i64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeF32)
|
|
case OpcodeF32DemoteF64:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF64); err != nil {
|
|
return fmt.Errorf("cannot pop the operand for %s: %v", OpcodeF32DemoteF64Name, err)
|
|
}
|
|
valueTypeStack.push(ValueTypeF32)
|
|
case OpcodeF64ConvertI32S, OpcodeF64ConvertI32U:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the i32 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeF64)
|
|
case OpcodeF64ConvertI64S, OpcodeF64ConvertI64U:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
|
|
return fmt.Errorf("cannot pop the i64 operand for %s: %v", InstructionName(op), err)
|
|
}
|
|
valueTypeStack.push(ValueTypeF64)
|
|
case OpcodeF64PromoteF32:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF32); err != nil {
|
|
return fmt.Errorf("cannot pop the operand for %s: %v", OpcodeF64PromoteF32Name, err)
|
|
}
|
|
valueTypeStack.push(ValueTypeF64)
|
|
case OpcodeI32ReinterpretF32:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF32); err != nil {
|
|
return fmt.Errorf("cannot pop the operand for %s: %v", OpcodeI32ReinterpretF32Name, err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeI64ReinterpretF64:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeF64); err != nil {
|
|
return fmt.Errorf("cannot pop the operand for %s: %v", OpcodeI64ReinterpretF64Name, err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI64)
|
|
case OpcodeF32ReinterpretI32:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the operand for %s: %v", OpcodeF32ReinterpretI32Name, err)
|
|
}
|
|
valueTypeStack.push(ValueTypeF32)
|
|
case OpcodeF64ReinterpretI64:
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
|
|
return fmt.Errorf("cannot pop the operand for %s: %v", OpcodeF64ReinterpretI64Name, err)
|
|
}
|
|
valueTypeStack.push(ValueTypeF64)
|
|
case OpcodeI32Extend8S, OpcodeI32Extend16S:
|
|
if err := enabledFeatures.Require(FeatureSignExtensionOps); err != nil {
|
|
return fmt.Errorf("%s invalid as %v", instructionNames[op], err)
|
|
}
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the operand for %s: %v", instructionNames[op], err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI32)
|
|
case OpcodeI64Extend8S, OpcodeI64Extend16S, OpcodeI64Extend32S:
|
|
if err := enabledFeatures.Require(FeatureSignExtensionOps); err != nil {
|
|
return fmt.Errorf("%s invalid as %v", instructionNames[op], err)
|
|
}
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI64); err != nil {
|
|
return fmt.Errorf("cannot pop the operand for %s: %v", instructionNames[op], err)
|
|
}
|
|
valueTypeStack.push(ValueTypeI64)
|
|
default:
|
|
return fmt.Errorf("invalid numeric instruction 0x%x", op)
|
|
}
|
|
} else if op == OpcodeBlock {
|
|
bt, num, err := decodeBlockType(types, bytes.NewReader(body[pc+1:]), enabledFeatures)
|
|
if err != nil {
|
|
return fmt.Errorf("read block: %w", err)
|
|
}
|
|
controlBlockStack = append(controlBlockStack, &controlBlock{
|
|
startAt: pc,
|
|
blockType: bt,
|
|
blockTypeBytes: num,
|
|
})
|
|
valueTypeStack.pushStackLimit(len(bt.Params))
|
|
pc += num
|
|
} else if op == OpcodeLoop {
|
|
bt, num, err := decodeBlockType(types, bytes.NewReader(body[pc+1:]), enabledFeatures)
|
|
if err != nil {
|
|
return fmt.Errorf("read block: %w", err)
|
|
}
|
|
controlBlockStack = append(controlBlockStack, &controlBlock{
|
|
startAt: pc,
|
|
blockType: bt,
|
|
blockTypeBytes: num,
|
|
op: op,
|
|
})
|
|
if err = valueTypeStack.popParams(op, bt.Params, false); err != nil {
|
|
return err
|
|
}
|
|
// Plus we have to push any block params again.
|
|
for _, p := range bt.Params {
|
|
valueTypeStack.push(p)
|
|
}
|
|
valueTypeStack.pushStackLimit(len(bt.Params))
|
|
pc += num
|
|
} else if op == OpcodeIf {
|
|
bt, num, err := decodeBlockType(types, bytes.NewReader(body[pc+1:]), enabledFeatures)
|
|
if err != nil {
|
|
return fmt.Errorf("read block: %w", err)
|
|
}
|
|
controlBlockStack = append(controlBlockStack, &controlBlock{
|
|
startAt: pc,
|
|
blockType: bt,
|
|
blockTypeBytes: num,
|
|
op: op,
|
|
})
|
|
if err = valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("cannot pop the operand for 'if': %v", err)
|
|
}
|
|
if err = valueTypeStack.popParams(op, bt.Params, false); err != nil {
|
|
return err
|
|
}
|
|
// Plus we have to push any block params again.
|
|
for _, p := range bt.Params {
|
|
valueTypeStack.push(p)
|
|
}
|
|
valueTypeStack.pushStackLimit(len(bt.Params))
|
|
pc += num
|
|
} else if op == OpcodeElse {
|
|
bl := controlBlockStack[len(controlBlockStack)-1]
|
|
bl.elseAt = pc
|
|
// Check the type soundness of the instructions *before* entering this else Op.
|
|
if err := valueTypeStack.popResults(OpcodeIf, bl.blockType.Results, true); err != nil {
|
|
return err
|
|
}
|
|
// Before entering instructions inside else, we pop all the values pushed by then block.
|
|
valueTypeStack.resetAtStackLimit()
|
|
// Plus we have to push any block params again.
|
|
for _, p := range bl.blockType.Params {
|
|
valueTypeStack.push(p)
|
|
}
|
|
} else if op == OpcodeEnd {
|
|
bl := controlBlockStack[len(controlBlockStack)-1]
|
|
bl.endAt = pc
|
|
controlBlockStack = controlBlockStack[:len(controlBlockStack)-1]
|
|
|
|
// OpcodeEnd can end a block or the function itself. Check to see what it is:
|
|
|
|
ifMissingElse := bl.op == OpcodeIf && bl.elseAt <= bl.startAt
|
|
if ifMissingElse {
|
|
// If this is the end of block without else, the number of block's results and params must be same.
|
|
// Otherwise, the value stack would result in the inconsistent state at runtime.
|
|
if !bytes.Equal(bl.blockType.Results, bl.blockType.Params) {
|
|
return typeCountError(false, OpcodeElseName, bl.blockType.Params, bl.blockType.Results)
|
|
}
|
|
// -1 skips else, to handle if block without else properly.
|
|
bl.elseAt = bl.endAt - 1
|
|
}
|
|
|
|
// Determine the block context
|
|
ctx := "" // the outer-most block: the function return
|
|
if bl.op == OpcodeIf && !ifMissingElse && bl.elseAt > 0 {
|
|
ctx = OpcodeElseName
|
|
} else if bl.op != 0 {
|
|
ctx = InstructionName(bl.op)
|
|
}
|
|
|
|
// Check return types match
|
|
if err := valueTypeStack.requireStackValues(false, ctx, bl.blockType.Results, true); err != nil {
|
|
return err
|
|
}
|
|
|
|
// Put the result types at the end after resetting at the stack limit
|
|
// since we might have Any type between the limit and the current top.
|
|
valueTypeStack.resetAtStackLimit()
|
|
for _, exp := range bl.blockType.Results {
|
|
valueTypeStack.push(exp)
|
|
}
|
|
// We exit if/loop/block, so reset the constraints on the stack manipulation
|
|
// on values previously pushed by outer blocks.
|
|
valueTypeStack.popStackLimit()
|
|
} else if op == OpcodeReturn {
|
|
// Same formatting as OpcodeEnd on the outer-most block
|
|
if err := valueTypeStack.requireStackValues(false, "", functionType.Results, false); err != nil {
|
|
return err
|
|
}
|
|
// return instruction is stack-polymorphic.
|
|
valueTypeStack.unreachable()
|
|
} else if op == OpcodeDrop {
|
|
_, err := valueTypeStack.pop()
|
|
if err != nil {
|
|
return fmt.Errorf("invalid drop: %v", err)
|
|
}
|
|
} else if op == OpcodeSelect {
|
|
if err := valueTypeStack.popAndVerifyType(ValueTypeI32); err != nil {
|
|
return fmt.Errorf("type mismatch on 3rd select operand: %v", err)
|
|
}
|
|
v1, err := valueTypeStack.pop()
|
|
if err != nil {
|
|
return fmt.Errorf("invalid select: %v", err)
|
|
}
|
|
v2, err := valueTypeStack.pop()
|
|
if err != nil {
|
|
return fmt.Errorf("invalid select: %v", err)
|
|
}
|
|
if v1 != v2 && v1 != valueTypeUnknown && v2 != valueTypeUnknown {
|
|
return fmt.Errorf("type mismatch on 1st and 2nd select operands")
|
|
}
|
|
if v1 == valueTypeUnknown {
|
|
valueTypeStack.push(v2)
|
|
} else {
|
|
valueTypeStack.push(v1)
|
|
}
|
|
} else if op == OpcodeUnreachable {
|
|
// unreachable instruction is stack-polymorphic.
|
|
valueTypeStack.unreachable()
|
|
} else if op == OpcodeNop {
|
|
} else {
|
|
return fmt.Errorf("invalid instruction 0x%x", op)
|
|
}
|
|
}
|
|
|
|
if len(controlBlockStack) > 0 {
|
|
return fmt.Errorf("ill-nested block exists")
|
|
}
|
|
if valueTypeStack.maximumStackPointer > maxStackValues {
|
|
return fmt.Errorf("function may have %d stack values, which exceeds limit %d", valueTypeStack.maximumStackPointer, maxStackValues)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
type valueTypeStack struct {
|
|
stack []ValueType
|
|
stackLimits []int
|
|
maximumStackPointer int
|
|
}
|
|
|
|
const (
|
|
// Only used in the analyzeFunction below.
|
|
valueTypeUnknown = ValueType(0xFF)
|
|
)
|
|
|
|
func (s *valueTypeStack) tryPop() (vt ValueType, limit int, ok bool) {
|
|
if len(s.stackLimits) > 0 {
|
|
limit = s.stackLimits[len(s.stackLimits)-1]
|
|
}
|
|
stackLen := len(s.stack)
|
|
if stackLen <= limit {
|
|
return
|
|
} else if stackLen == limit+1 && s.stack[limit] == valueTypeUnknown {
|
|
vt = valueTypeUnknown
|
|
ok = true
|
|
return
|
|
} else {
|
|
vt = s.stack[stackLen-1]
|
|
s.stack = s.stack[:stackLen-1]
|
|
ok = true
|
|
return
|
|
}
|
|
}
|
|
|
|
func (s *valueTypeStack) pop() (ValueType, error) {
|
|
if vt, limit, ok := s.tryPop(); ok {
|
|
return vt, nil
|
|
} else {
|
|
return 0, fmt.Errorf("invalid operation: trying to pop at %d with limit %d", len(s.stack), limit)
|
|
}
|
|
}
|
|
|
|
// popAndVerifyType returns an error if the stack value is unexpected.
|
|
func (s *valueTypeStack) popAndVerifyType(expected ValueType) error {
|
|
have, _, ok := s.tryPop()
|
|
if !ok {
|
|
return fmt.Errorf("%s missing", ValueTypeName(expected))
|
|
}
|
|
if have != expected && have != valueTypeUnknown && expected != valueTypeUnknown {
|
|
return fmt.Errorf("type mismatch: expected %s, but was %s", ValueTypeName(expected), ValueTypeName(have))
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (s *valueTypeStack) push(v ValueType) {
|
|
s.stack = append(s.stack, v)
|
|
if sp := len(s.stack); sp > s.maximumStackPointer {
|
|
s.maximumStackPointer = sp
|
|
}
|
|
}
|
|
|
|
func (s *valueTypeStack) unreachable() {
|
|
s.resetAtStackLimit()
|
|
s.stack = append(s.stack, valueTypeUnknown)
|
|
}
|
|
|
|
func (s *valueTypeStack) resetAtStackLimit() {
|
|
if len(s.stackLimits) != 0 {
|
|
s.stack = s.stack[:s.stackLimits[len(s.stackLimits)-1]]
|
|
} else {
|
|
s.stack = []ValueType{}
|
|
}
|
|
}
|
|
|
|
func (s *valueTypeStack) popStackLimit() {
|
|
if len(s.stackLimits) != 0 {
|
|
s.stackLimits = s.stackLimits[:len(s.stackLimits)-1]
|
|
}
|
|
}
|
|
|
|
// pushStackLimit pushes the control frame's bottom of the stack.
|
|
func (s *valueTypeStack) pushStackLimit(params int) {
|
|
limit := len(s.stack) - params
|
|
s.stackLimits = append(s.stackLimits, limit)
|
|
}
|
|
|
|
func (s *valueTypeStack) popParams(oc Opcode, want []ValueType, checkAboveLimit bool) error {
|
|
return s.requireStackValues(true, InstructionName(oc), want, checkAboveLimit)
|
|
}
|
|
|
|
func (s *valueTypeStack) popResults(oc Opcode, want []ValueType, checkAboveLimit bool) error {
|
|
return s.requireStackValues(false, InstructionName(oc), want, checkAboveLimit)
|
|
}
|
|
|
|
func (s *valueTypeStack) requireStackValues(
|
|
isParam bool,
|
|
context string,
|
|
want []ValueType,
|
|
checkAboveLimit bool,
|
|
) error {
|
|
limit := 0
|
|
if len(s.stackLimits) > 0 {
|
|
limit = s.stackLimits[len(s.stackLimits)-1]
|
|
}
|
|
// Iterate backwards as we are comparing the desired slice against stack value types.
|
|
countWanted := len(want)
|
|
|
|
// First, check if there are enough values on the stack.
|
|
have := make([]ValueType, 0, countWanted)
|
|
for i := countWanted - 1; i >= 0; i-- {
|
|
popped, _, ok := s.tryPop()
|
|
if !ok {
|
|
if len(have) > len(want) {
|
|
return typeCountError(isParam, context, have, want)
|
|
}
|
|
return typeCountError(isParam, context, have, want)
|
|
}
|
|
have = append(have, popped)
|
|
}
|
|
|
|
// Now, check if there are too many values.
|
|
if checkAboveLimit {
|
|
if !(limit == len(s.stack) || (limit+1 == len(s.stack) && s.stack[limit] == valueTypeUnknown)) {
|
|
return typeCountError(isParam, context, append(s.stack, want...), want)
|
|
}
|
|
}
|
|
|
|
// Finally, check the types of the values:
|
|
for i, v := range have {
|
|
nextWant := want[countWanted-i-1] // have is in reverse order (stack)
|
|
if v != nextWant && v != valueTypeUnknown && nextWant != valueTypeUnknown {
|
|
return typeMismatchError(isParam, context, v, nextWant, i)
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// typeMismatchError returns an error similar to go compiler's error on type mismatch.
|
|
func typeMismatchError(isParam bool, context string, have ValueType, want ValueType, i int) error {
|
|
var ret strings.Builder
|
|
ret.WriteString("cannot use ")
|
|
ret.WriteString(ValueTypeName(have))
|
|
if context != "" {
|
|
ret.WriteString(" in ")
|
|
ret.WriteString(context)
|
|
ret.WriteString(" block")
|
|
}
|
|
if isParam {
|
|
ret.WriteString(" as param")
|
|
} else {
|
|
ret.WriteString(" as result")
|
|
}
|
|
ret.WriteString("[")
|
|
ret.WriteString(strconv.Itoa(i))
|
|
ret.WriteString("] type ")
|
|
ret.WriteString(ValueTypeName(want))
|
|
return errors.New(ret.String())
|
|
}
|
|
|
|
// typeCountError returns an error similar to go compiler's error on type count mismatch.
|
|
func typeCountError(isParam bool, context string, have []ValueType, want []ValueType) error {
|
|
var ret strings.Builder
|
|
if len(have) > len(want) {
|
|
ret.WriteString("too many ")
|
|
} else {
|
|
ret.WriteString("not enough ")
|
|
}
|
|
if isParam {
|
|
ret.WriteString("params")
|
|
} else {
|
|
ret.WriteString("results")
|
|
}
|
|
if context != "" {
|
|
if isParam {
|
|
ret.WriteString(" for ")
|
|
} else {
|
|
ret.WriteString(" in ")
|
|
}
|
|
ret.WriteString(context)
|
|
ret.WriteString(" block")
|
|
}
|
|
ret.WriteString("\n\thave (")
|
|
writeValueTypes(have, &ret)
|
|
ret.WriteString(")\n\twant (")
|
|
writeValueTypes(want, &ret)
|
|
ret.WriteByte(')')
|
|
return errors.New(ret.String())
|
|
}
|
|
|
|
func writeValueTypes(vts []ValueType, ret *strings.Builder) {
|
|
switch len(vts) {
|
|
case 0:
|
|
case 1:
|
|
ret.WriteString(api.ValueTypeName(vts[0]))
|
|
default:
|
|
ret.WriteString(api.ValueTypeName(vts[0]))
|
|
for _, vt := range vts[1:] {
|
|
ret.WriteString(", ")
|
|
ret.WriteString(api.ValueTypeName(vt))
|
|
}
|
|
}
|
|
}
|
|
|
|
func (s *valueTypeStack) String() string {
|
|
var typeStrs, limits []string
|
|
for _, v := range s.stack {
|
|
var str string
|
|
if v == valueTypeUnknown {
|
|
str = "unknown"
|
|
} else if v == ValueTypeI32 {
|
|
str = "i32"
|
|
} else if v == ValueTypeI64 {
|
|
str = "i64"
|
|
} else if v == ValueTypeF32 {
|
|
str = "f32"
|
|
} else if v == ValueTypeF64 {
|
|
str = "f64"
|
|
}
|
|
typeStrs = append(typeStrs, str)
|
|
}
|
|
for _, d := range s.stackLimits {
|
|
limits = append(limits, fmt.Sprintf("%d", d))
|
|
}
|
|
return fmt.Sprintf("{stack: [%s], limits: [%s]}",
|
|
strings.Join(typeStrs, ", "), strings.Join(limits, ","))
|
|
}
|
|
|
|
type controlBlock struct {
|
|
startAt, elseAt, endAt uint64
|
|
blockType *FunctionType
|
|
blockTypeBytes uint64
|
|
// op is zero when the outermost block
|
|
op Opcode
|
|
}
|
|
|
|
func decodeBlockType(types []*FunctionType, r *bytes.Reader, enabledFeatures Features) (*FunctionType, uint64, error) {
|
|
return decodeBlockTypeImpl(func(index int64) (*FunctionType, error) {
|
|
if index < 0 || (index >= int64(len(types))) {
|
|
return nil, fmt.Errorf("type index out of range: %d", index)
|
|
}
|
|
return types[index], nil
|
|
}, r, enabledFeatures)
|
|
}
|
|
|
|
// DecodeBlockType is exported for use in the compiler
|
|
func DecodeBlockType(types []*TypeInstance, r *bytes.Reader, enabledFeatures Features) (*FunctionType, uint64, error) {
|
|
return decodeBlockTypeImpl(func(index int64) (*FunctionType, error) {
|
|
if index < 0 || (index >= int64(len(types))) {
|
|
return nil, fmt.Errorf("type index out of range: %d", index)
|
|
}
|
|
return types[index].Type, nil
|
|
}, r, enabledFeatures)
|
|
}
|
|
|
|
// decodeBlockTypeImpl decodes the type index from a positive 33-bit signed integer. Negative numbers indicate up to one
|
|
// WebAssembly 1.0 (20191205) compatible result type. Positive numbers are decoded when `enabledFeatures` include
|
|
// FeatureMultiValue and include an index in the Module.TypeSection.
|
|
//
|
|
// See https://www.w3.org/TR/2019/REC-wasm-core-1-20191205/#binary-blocktype
|
|
// See https://github.com/WebAssembly/spec/blob/main/proposals/multi-value/Overview.md
|
|
func decodeBlockTypeImpl(functionTypeResolver func(index int64) (*FunctionType, error), r *bytes.Reader, enabledFeatures Features) (*FunctionType, uint64, error) {
|
|
raw, num, err := leb128.DecodeInt33AsInt64(r)
|
|
if err != nil {
|
|
return nil, 0, fmt.Errorf("decode int33: %w", err)
|
|
}
|
|
|
|
var ret *FunctionType
|
|
switch raw {
|
|
case -64: // 0x40 in original byte = nil
|
|
ret = &FunctionType{}
|
|
case -1: // 0x7f in original byte = i32
|
|
ret = &FunctionType{Results: []ValueType{ValueTypeI32}}
|
|
case -2: // 0x7e in original byte = i64
|
|
ret = &FunctionType{Results: []ValueType{ValueTypeI64}}
|
|
case -3: // 0x7d in original byte = f32
|
|
ret = &FunctionType{Results: []ValueType{ValueTypeF32}}
|
|
case -4: // 0x7c in original byte = f64
|
|
ret = &FunctionType{Results: []ValueType{ValueTypeF64}}
|
|
default:
|
|
if err = enabledFeatures.Require(FeatureMultiValue); err != nil {
|
|
return nil, num, fmt.Errorf("block with function type return invalid as %v", err)
|
|
}
|
|
ret, err = functionTypeResolver(raw)
|
|
}
|
|
return ret, num, err
|
|
}
|