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tcg/ppc: Look for shifted constants

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Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Richard Henderson 2017-07-31 04:54:02 +00:00
parent 5964fca8a1
commit 77bfc7c0b4
1 changed files with 48 additions and 10 deletions
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58
tcg/ppc/tcg-target.inc.c
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@ -593,11 +593,26 @@ static inline void tcg_out_shri64(TCGContext *s, TCGReg dst, TCGReg src, int c)
tcg_out_rld(s, RLDICL, dst, src, 64 - c, c);
}
/* Emit a move into ret of arg, if it can be done in one insn. */
static bool tcg_out_movi_one(TCGContext *s, TCGReg ret, tcg_target_long arg)
{
if (arg == (int16_t)arg) {
tcg_out32(s, ADDI | TAI(ret, 0, arg));
return true;
}
if (arg == (int32_t)arg && (arg & 0xffff) == 0) {
tcg_out32(s, ADDIS | TAI(ret, 0, arg >> 16));
return true;
}
return false;
}
static void tcg_out_movi_int(TCGContext *s, TCGType type, TCGReg ret,
tcg_target_long arg, bool in_prologue)
{
intptr_t tb_diff;
int32_t high;
tcg_target_long tmp;
int shift;
tcg_debug_assert(TCG_TARGET_REG_BITS == 64 || type == TCG_TYPE_I32);
@ -606,8 +621,7 @@ static void tcg_out_movi_int(TCGContext *s, TCGType type, TCGReg ret,
}
/* Load 16-bit immediates with one insn. */
if (arg == (int16_t)arg) {
tcg_out32(s, ADDI | TAI(ret, 0, arg));
if (tcg_out_movi_one(s, ret, arg)) {
return;
}
@ -618,12 +632,11 @@ static void tcg_out_movi_int(TCGContext *s, TCGType type, TCGReg ret,
return;
}
/* Load 32-bit immediates with two insns. */
/* Load 32-bit immediates with two insns. Note that we've already
eliminated bare ADDIS, so we know both insns are required. */
if (TCG_TARGET_REG_BITS == 32 || arg == (int32_t)arg) {
tcg_out32(s, ADDIS | TAI(ret, 0, arg >> 16));
if (arg & 0xffff) {
tcg_out32(s, ORI | SAI(ret, ret, arg));
}
tcg_out32(s, ORI | SAI(ret, ret, arg));
return;
}
if (arg == (uint32_t)arg && !(arg & 0x8000)) {
@ -632,15 +645,40 @@ static void tcg_out_movi_int(TCGContext *s, TCGType type, TCGReg ret,
return;
}
/* Load masked 16-bit value. */
if (arg > 0 && (arg & 0x8000)) {
tmp = arg | 0x7fff;
if ((tmp & (tmp + 1)) == 0) {
int mb = clz64(tmp + 1) + 1;
tcg_out32(s, ADDI | TAI(ret, 0, arg));
tcg_out_rld(s, RLDICL, ret, ret, 0, mb);
return;
}
}
/* Load common masks with 2 insns. */
shift = ctz64(arg);
tmp = arg >> shift;
if (tmp == (int16_t)tmp) {
tcg_out32(s, ADDI | TAI(ret, 0, tmp));
tcg_out_shli64(s, ret, ret, shift);
return;
}
shift = clz64(arg);
if (tcg_out_movi_one(s, ret, arg << shift)) {
tcg_out_shri64(s, ret, ret, shift);
return;
}
/* Load addresses within 2GB of TB with 2 (or rarely 3) insns. */
if (!in_prologue && USE_REG_TB && tb_diff == (int32_t)tb_diff) {
tcg_out_mem_long(s, ADDI, ADD, ret, TCG_REG_TB, tb_diff);
return;
}
high = arg >> 31 >> 1;
tcg_out_movi(s, TCG_TYPE_I32, ret, high);
if (high) {
tmp = arg >> 31 >> 1;
tcg_out_movi(s, TCG_TYPE_I32, ret, tmp);
if (tmp) {
tcg_out_shli64(s, ret, ret, 32);
}
if (arg & 0xffff0000) {