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tcg-i386: Try pc-relative lea for constant formation

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Use a 7 byte lea before the ultimate 10 byte movq.

Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Richard Henderson 2013-07-25 10:00:41 -10:00
parent ac26eb69a3
commit 8023ccda07
1 changed files with 20 additions and 5 deletions
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25
tcg/i386/tcg-target.c
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@ -541,19 +541,34 @@ static inline void tcg_out_mov(TCGContext *s, TCGType type,
static void tcg_out_movi(TCGContext *s, TCGType type,
TCGReg ret, tcg_target_long arg)
{
tcg_target_long diff;
if (arg == 0) {
tgen_arithr(s, ARITH_XOR, ret, ret);
return;
} else if (arg == (uint32_t)arg || type == TCG_TYPE_I32) {
}
if (arg == (uint32_t)arg || type == TCG_TYPE_I32) {
tcg_out_opc(s, OPC_MOVL_Iv + LOWREGMASK(ret), 0, ret, 0);
tcg_out32(s, arg);
} else if (arg == (int32_t)arg) {
return;
}
if (arg == (int32_t)arg) {
tcg_out_modrm(s, OPC_MOVL_EvIz + P_REXW, 0, ret);
tcg_out32(s, arg);
} else {
tcg_out_opc(s, OPC_MOVL_Iv + P_REXW + LOWREGMASK(ret), 0, ret, 0);
tcg_out64(s, arg);
return;
}
/* Try a 7 byte pc-relative lea before the 10 byte movq. */
diff = arg - ((tcg_target_long)s->code_ptr + 7);
if (diff == (int32_t)diff) {
tcg_out_opc(s, OPC_LEA | P_REXW, ret, 0, 0);
tcg_out8(s, (LOWREGMASK(ret) << 3) | 5);
tcg_out32(s, diff);
return;
}
tcg_out_opc(s, OPC_MOVL_Iv + P_REXW + LOWREGMASK(ret), 0, ret, 0);
tcg_out64(s, arg);
}
static inline void tcg_out_pushi(TCGContext *s, tcg_target_long val)