9c70781236
Bump CI Go versions to 1.16 and 1.17. Update build tags with `go:build` equivalents. Upgrade asmfmt tool for new `go:build` support. Updates #183
40 lines
787 B
Go
40 lines
787 B
Go
//go:build ignore
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// +build ignore
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package main
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import (
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. "github.com/mmcloughlin/avo/build"
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. "github.com/mmcloughlin/avo/operand"
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)
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func main() {
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TEXT("Sum", NOSPLIT, "func(xs []uint64) uint64")
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Doc("Sum returns the sum of the elements in xs.")
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ptr := Load(Param("xs").Base(), GP64())
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n := Load(Param("xs").Len(), GP64())
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Comment("Initialize sum register to zero.")
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s := GP64()
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XORQ(s, s)
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Label("loop")
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Comment("Loop until zero bytes remain.")
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CMPQ(n, Imm(0))
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JE(LabelRef("done"))
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Comment("Load from pointer and add to running sum.")
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ADDQ(Mem{Base: ptr}, s)
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Comment("Advance pointer, decrement byte count.")
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ADDQ(Imm(8), ptr)
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DECQ(n)
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JMP(LabelRef("loop"))
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Label("done")
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Comment("Store sum to return value.")
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Store(s, ReturnIndex(0))
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RET()
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Generate()
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}
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