304c7425d2
Brings the TEXT() function signature closer to how the directive works in assembly. Also update almost all examples to use NOSPLIT. Closes #11
sha1
SHA-1 in avo.
Compare to the crypto/sha1 assembly.
func main() {
TEXT("block", "func(h *[5]uint32, m []byte)")
Doc("block SHA-1 hashes the 64-byte message m into the running state h.")
h := Mem{Base: Load(Param("h"), GP64())}
m := Mem{Base: Load(Param("m").Base(), GP64())}
// Store message values on the stack.
w := AllocLocal(64)
W := func(r int) Mem { return w.Offset((r % 16) * 4) }
// Load initial hash.
h0, h1, h2, h3, h4 := GP32(), GP32(), GP32(), GP32(), GP32()
MOVL(h.Offset(0), h0)
MOVL(h.Offset(4), h1)
MOVL(h.Offset(8), h2)
MOVL(h.Offset(12), h3)
MOVL(h.Offset(16), h4)
// Initialize registers.
a, b, c, d, e := GP32(), GP32(), GP32(), GP32(), GP32()
MOVL(h0, a)
MOVL(h1, b)
MOVL(h2, c)
MOVL(h3, d)
MOVL(h4, e)
// Generate round updates.
quarter := []struct {
F func(Register, Register, Register) Register
K uint32
}{
{choose, 0x5a827999},
{xor, 0x6ed9eba1},
{majority, 0x8f1bbcdc},
{xor, 0xca62c1d6},
}
for r := 0; r < 80; r++ {
q := quarter[r/20]
// Load message value.
u := GP32()
if r < 16 {
MOVL(m.Offset(4*r), u)
BSWAPL(u)
} else {
MOVL(W(r-3), u)
XORL(W(r-8), u)
XORL(W(r-14), u)
XORL(W(r-16), u)
ROLL(U8(1), u)
}
MOVL(u, W(r))
// Compute the next state register.
t := GP32()
MOVL(a, t)
ROLL(U8(5), t)
ADDL(q.F(b, c, d), t)
ADDL(e, t)
ADDL(U32(q.K), t)
ADDL(u, t)
// Update registers.
ROLL(Imm(30), b)
a, b, c, d, e = t, a, b, c, d
}
// Final add.
ADDL(a, h0)
ADDL(b, h1)
ADDL(c, h2)
ADDL(d, h3)
ADDL(e, h4)
// Store results back.
MOVL(h0, h.Offset(0))
MOVL(h1, h.Offset(4))
MOVL(h2, h.Offset(8))
MOVL(h3, h.Offset(12))
MOVL(h4, h.Offset(16))
RET()
Generate()
}