tcg/i386: Store out-of-range call targets in constant pool

Already it saves 2 bytes per call, but also the constant pool
entry may well be shared across multiple calls.

Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Richard Henderson 2017-07-20 19:56:42 -10:00
parent 57a269469d
commit 4e45f23943
2 changed files with 16 additions and 3 deletions

View File

@ -189,5 +189,6 @@ static inline void tb_target_set_jmp_target(uintptr_t tc_ptr,
#ifdef CONFIG_SOFTMMU
#define TCG_TARGET_NEED_LDST_LABELS
#endif
#define TCG_TARGET_NEED_POOL_LABELS
#endif

View File

@ -22,6 +22,8 @@
* THE SOFTWARE.
*/
#include "tcg-pool.inc.c"
#ifdef CONFIG_DEBUG_TCG
static const char * const tcg_target_reg_names[TCG_TARGET_NB_REGS] = {
#if TCG_TARGET_REG_BITS == 64
@ -1180,9 +1182,14 @@ static void tcg_out_branch(TCGContext *s, int call, tcg_insn_unit *dest)
tcg_out_opc(s, call ? OPC_CALL_Jz : OPC_JMP_long, 0, 0, 0);
tcg_out32(s, disp);
} else {
tcg_out_movi(s, TCG_TYPE_PTR, TCG_REG_R10, (uintptr_t)dest);
tcg_out_modrm(s, OPC_GRP5,
call ? EXT5_CALLN_Ev : EXT5_JMPN_Ev, TCG_REG_R10);
/* rip-relative addressing into the constant pool.
This is 6 + 8 = 14 bytes, as compared to using an
an immediate load 10 + 6 = 16 bytes, plus we may
be able to re-use the pool constant for more calls. */
tcg_out_opc(s, OPC_GRP5, 0, 0, 0);
tcg_out8(s, (call ? EXT5_CALLN_Ev : EXT5_JMPN_Ev) << 3 | 5);
new_pool_label(s, (uintptr_t)dest, R_386_PC32, s->code_ptr, -4);
tcg_out32(s, 0);
}
}
@ -2595,6 +2602,11 @@ static void tcg_target_qemu_prologue(TCGContext *s)
#endif
}
static void tcg_out_nop_fill(tcg_insn_unit *p, int count)
{
memset(p, 0x90, count);
}
static void tcg_target_init(TCGContext *s)
{
#ifdef CONFIG_CPUID_H