tcg/mips: Aggressively use the constant pool for n64 calls

Repeated calls to a single helper are common -- especially
the ones for softmmu memory access.  Prefer the constant pool
to longer sequences to increase sharing.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2021-08-06 13:17:20 -10:00
parent 48c12ba748
commit 4316de32e7

View file

@ -1101,9 +1101,19 @@ static void tcg_out_movcond(TCGContext *s, TCGCond cond, TCGReg ret,
static void tcg_out_call_int(TCGContext *s, const tcg_insn_unit *arg, bool tail)
{
/* Note that the ABI requires the called function's address to be
loaded into T9, even if a direct branch is in range. */
tcg_out_movi(s, TCG_TYPE_PTR, TCG_REG_T9, (uintptr_t)arg);
/*
* Note that __mips_abicalls requires the called function's address
* to be loaded into $25 (t9), even if a direct branch is in range.
*
* For n64, always drop the pointer into the constant pool.
* We can re-use helper addresses often and do not want any
* of the longer sequences tcg_out_movi may try.
*/
if (sizeof(uintptr_t) == 8) {
tcg_out_movi_pool(s, TCG_REG_T9, (uintptr_t)arg, TCG_REG_TB);
} else {
tcg_out_movi(s, TCG_TYPE_PTR, TCG_REG_T9, (uintptr_t)arg);
}
/* But do try a direct branch, allowing the cpu better insn prefetch. */
if (tail) {