tcg/aarch64: Use constant pool for movi

Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Richard Henderson 2017-07-26 00:29:49 -07:00
parent a534bb15f3
commit 55129955e9
2 changed files with 34 additions and 31 deletions

View File

@ -125,5 +125,6 @@ void tb_target_set_jmp_target(uintptr_t, uintptr_t, uintptr_t);
#ifdef CONFIG_SOFTMMU
#define TCG_TARGET_NEED_LDST_LABELS
#endif
#define TCG_TARGET_NEED_POOL_LABELS
#endif /* AARCH64_TCG_TARGET_H */

View File

@ -10,6 +10,7 @@
* See the COPYING file in the top-level directory for details.
*/
#include "tcg-pool.inc.c"
#include "qemu/bitops.h"
/* We're going to re-use TCGType in setting of the SF bit, which controls
@ -587,9 +588,11 @@ static void tcg_out_logicali(TCGContext *s, AArch64Insn insn, TCGType ext,
static void tcg_out_movi(TCGContext *s, TCGType type, TCGReg rd,
tcg_target_long value)
{
int i, wantinv, shift;
tcg_target_long svalue = value;
tcg_target_long ivalue = ~value;
tcg_target_long t0, t1, t2;
int s0, s1;
AArch64Insn opc;
/* For 32-bit values, discard potential garbage in value. For 64-bit
values within [2**31, 2**32-1], we can create smaller sequences by
@ -638,38 +641,29 @@ static void tcg_out_movi(TCGContext *s, TCGType type, TCGReg rd,
}
}
/* Would it take fewer insns to begin with MOVN? For the value and its
inverse, count the number of 16-bit lanes that are 0. */
for (i = wantinv = 0; i < 64; i += 16) {
tcg_target_long mask = 0xffffull << i;
wantinv -= ((value & mask) == 0);
wantinv += ((ivalue & mask) == 0);
/* Would it take fewer insns to begin with MOVN? */
if (ctpop64(value) >= 32) {
t0 = ivalue;
opc = I3405_MOVN;
} else {
t0 = value;
opc = I3405_MOVZ;
}
s0 = ctz64(t0) & (63 & -16);
t1 = t0 & ~(0xffffUL << s0);
s1 = ctz64(t1) & (63 & -16);
t2 = t1 & ~(0xffffUL << s1);
if (t2 == 0) {
tcg_out_insn_3405(s, opc, type, rd, t0 >> s0, s0);
if (t1 != 0) {
tcg_out_insn(s, 3405, MOVK, type, rd, value >> s1, s1);
}
return;
}
if (wantinv <= 0) {
/* Find the lowest lane that is not 0x0000. */
shift = ctz64(value) & (63 & -16);
tcg_out_insn(s, 3405, MOVZ, type, rd, value >> shift, shift);
/* Clear out the lane that we just set. */
value &= ~(0xffffUL << shift);
/* Iterate until all non-zero lanes have been processed. */
while (value) {
shift = ctz64(value) & (63 & -16);
tcg_out_insn(s, 3405, MOVK, type, rd, value >> shift, shift);
value &= ~(0xffffUL << shift);
}
} else {
/* Like above, but with the inverted value and MOVN to start. */
shift = ctz64(ivalue) & (63 & -16);
tcg_out_insn(s, 3405, MOVN, type, rd, ivalue >> shift, shift);
ivalue &= ~(0xffffUL << shift);
while (ivalue) {
shift = ctz64(ivalue) & (63 & -16);
/* Provide MOVK with the non-inverted value. */
tcg_out_insn(s, 3405, MOVK, type, rd, ~(ivalue >> shift), shift);
ivalue &= ~(0xffffUL << shift);
}
}
/* For more than 2 insns, dump it into the constant pool. */
new_pool_label(s, value, R_AARCH64_CONDBR19, s->code_ptr, 0);
tcg_out_insn(s, 3305, LDR, 0, rd);
}
/* Define something more legible for general use. */
@ -2030,6 +2024,14 @@ static void tcg_target_qemu_prologue(TCGContext *s)
tcg_out_insn(s, 3207, RET, TCG_REG_LR);
}
static void tcg_out_nop_fill(tcg_insn_unit *p, int count)
{
int i;
for (i = 0; i < count; ++i) {
p[i] = NOP;
}
}
typedef struct {
DebugFrameHeader h;
uint8_t fde_def_cfa[4];