66 lines
1.6 KiB
Go
66 lines
1.6 KiB
Go
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//go:build amd64 && !appengine && !noasm && gc
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// +build amd64,!appengine,!noasm,gc
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package zstd
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import (
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"fmt"
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)
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type buildDtableAsmContext struct {
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// inputs
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stateTable *uint16
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norm *int16
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dt *uint64
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// outputs --- set by the procedure in the case of error;
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// for interpretation please see the error handling part below
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errParam1 uint64
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errParam2 uint64
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}
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// buildDtable_asm is an x86 assembly implementation of fseDecoder.buildDtable.
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// Function returns non-zero exit code on error.
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//
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//go:noescape
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func buildDtable_asm(s *fseDecoder, ctx *buildDtableAsmContext) int
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// please keep in sync with _generate/gen_fse.go
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const (
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errorCorruptedNormalizedCounter = 1
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errorNewStateTooBig = 2
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errorNewStateNoBits = 3
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)
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// buildDtable will build the decoding table.
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func (s *fseDecoder) buildDtable() error {
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ctx := buildDtableAsmContext{
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stateTable: &s.stateTable[0],
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norm: &s.norm[0],
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dt: (*uint64)(&s.dt[0]),
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}
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code := buildDtable_asm(s, &ctx)
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if code != 0 {
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switch code {
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case errorCorruptedNormalizedCounter:
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position := ctx.errParam1
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return fmt.Errorf("corrupted input (position=%d, expected 0)", position)
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case errorNewStateTooBig:
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newState := decSymbol(ctx.errParam1)
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size := ctx.errParam2
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return fmt.Errorf("newState (%d) outside table size (%d)", newState, size)
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case errorNewStateNoBits:
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newState := decSymbol(ctx.errParam1)
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oldState := decSymbol(ctx.errParam2)
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return fmt.Errorf("newState (%d) == oldState (%d) and no bits", newState, oldState)
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default:
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return fmt.Errorf("buildDtable_asm returned unhandled nonzero code = %d", code)
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}
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}
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return nil
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}
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