Hi Jan, Uros,
i386.md has
(define_insn "*sse_prologue_save_insn"
[(set (mem:BLK (plus:DI (match_operand:DI 0 "register_operand" "R")
(match_operand:DI 4 "const_int_operand" "n")))
(unspec:BLK [(reg:DI 21)
(reg:DI 22)
(reg:DI 23)
(reg:DI 24)
(reg:DI 25)
(reg:DI 26)
(reg:DI 27)
(reg:DI 28)] UNSPEC_SSE_PROLOGUE_SAVE))
(use (match_operand:DI 1 "register_operand" "r"))
(use (match_operand:DI 2 "const_int_operand" "i"))
(use (label_ref:DI (match_operand 3 "" "X")))]
"TARGET_64BIT
&& INTVAL (operands[4]) + SSE_REGPARM_MAX * 16 - 16 < 128
&& INTVAL (operands[4]) + INTVAL (operands[2]) * 16 >= -128"
{
...
}
[(set_attr "type" "other")
(set_attr "length_immediate" "0")
(set_attr "length_address" "0")
(set_attr "length" "135")
(set_attr "memory" "store")
(set_attr "modrm" "0")
(set_attr "mode" "DI")])
Why is the length 135? I saw
jmp *%rdx # 12 *sse_prologue_save_insn [length = 135]
movaps %xmm7, -15(%rax)
movaps %xmm6, -31(%rax)
movaps %xmm5, -47(%rax)
movaps %xmm4, -63(%rax)
movaps %xmm3, -79(%rax)
movaps %xmm2, -95(%rax)
movaps %xmm1, -111(%rax)
movaps %xmm0, -127(%rax)
which is 34 bytes.
H.J.
