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//go:build ignore
// +build ignore
package main
import (
"strconv"
. "github.com/mmcloughlin/avo/build"
. "github.com/mmcloughlin/avo/operand"
. "github.com/mmcloughlin/avo/reg"
)
func main() {
// n is the number of 8-bit registers to use.
// 15 low-byte registers (excluding SP)
// 4 high-byte registers AH,BH,CH,DH
const n = 19
TEXT("GP8", NOSPLIT, "func() uint8")
Doc("GP8 returns the sum 1+2+...+" + strconv.Itoa(n) + " using " + strconv.Itoa(n) + " distinct 8-bit registers.")
// Allocate registers and initialize.
x := make([]Register, n)
i := 0
// Low byte registers.
for ; i < 15; i++ {
x[i] = GP8L()
MOVB(U8(i+1), x[i])
}
// High byte registers.
for ; i < n; i++ {
x[i] = GP8H()
MOVB(U8(i+1), x[i])
}
// Sum them up.
for i := 1; i < n; i++ {
ADDB(x[i], x[0])
}
// Return.
Store(x[0], ReturnIndex(0))
RET()
Generate()
}
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