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//go:build !noasm && gc && amd64
// +build !noasm,gc,amd64
package sha1cd
import (
"math"
"unsafe"
shared "github.com/pjbgf/sha1cd/internal"
)
type sliceHeader struct {
base uintptr
len int
cap int
}
// blockAMD64 hashes the message p into the current state in dig.
// Both m1 and cs are used to store intermediate results which are used by the collision detection logic.
//
//go:noescape
func blockAMD64(dig *digest, p sliceHeader, m1 []uint32, cs [][5]uint32)
func block(dig *digest, p []byte) {
m1 := [shared.Rounds]uint32{}
cs := [shared.PreStepState][shared.WordBuffers]uint32{}
for len(p) >= shared.Chunk {
// Only send a block to be processed, as the collission detection
// works on a block by block basis.
ips := sliceHeader{
base: uintptr(unsafe.Pointer(&p[0])),
len: int(math.Min(float64(len(p)), float64(shared.Chunk))),
cap: shared.Chunk,
}
blockAMD64(dig, ips, m1[:], cs[:])
col := checkCollision(m1, cs, dig.h)
if col {
dig.col = true
blockAMD64(dig, ips, m1[:], cs[:])
blockAMD64(dig, ips, m1[:], cs[:])
}
p = p[shared.Chunk:]
}
}
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