fb0b311844
Global constants can be defined in wasm or in ModuleBuilder. In either case, they end up being decoded and interpreted during instantiation. This chooses signed encoding to avoid surprises. A more comprehensive explanation was added to RATIONALE.md, but the motivation was a global 100 coming out negative. Signed-off-by: Adrian Cole <adrian@tetrate.io>
32 lines
817 B
Go
32 lines
817 B
Go
package ieee754
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import (
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"encoding/binary"
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"io"
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"math"
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)
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// DecodeFloat32 decodes a float32 in IEEE 754 binary representation.
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// See https://www.w3.org/TR/2019/REC-wasm-core-1-20191205/#floating-point%E2%91%A2
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func DecodeFloat32(r io.Reader) (float32, error) {
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buf := make([]byte, 4)
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_, err := io.ReadFull(r, buf)
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if err != nil {
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return 0, err
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}
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raw := binary.LittleEndian.Uint32(buf)
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return math.Float32frombits(raw), nil
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}
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// DecodeFloat64 decodes a float64 in IEEE 754 binary representation.
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// See https://www.w3.org/TR/2019/REC-wasm-core-1-20191205/#floating-point%E2%91%A2
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func DecodeFloat64(r io.Reader) (float64, error) {
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buf := make([]byte, 8)
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_, err := io.ReadFull(r, buf)
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if err != nil {
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return 0, err
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}
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raw := binary.LittleEndian.Uint64(buf)
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return math.Float64frombits(raw), nil
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}
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