tcg/i386: Introduce tcg_out_testi

Split out a helper for choosing testb vs testl.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2022-11-08 14:30:27 +11:00
parent 3c2c35e23e
commit a48f1c7415

View file

@ -1751,6 +1751,23 @@ static void tcg_out_nopn(TCGContext *s, int n)
tcg_out8(s, 0x90); tcg_out8(s, 0x90);
} }
/* Test register R vs immediate bits I, setting Z flag for EQ/NE. */
static void __attribute__((unused))
tcg_out_testi(TCGContext *s, TCGReg r, uint32_t i)
{
/*
* This is used for testing alignment, so we can usually use testb.
* For i686, we have to use testl for %esi/%edi.
*/
if (i <= 0xff && (TCG_TARGET_REG_BITS == 64 || r < 4)) {
tcg_out_modrm(s, OPC_GRP3_Eb | P_REXB_RM, EXT3_TESTi, r);
tcg_out8(s, i);
} else {
tcg_out_modrm(s, OPC_GRP3_Ev, EXT3_TESTi, r);
tcg_out32(s, i);
}
}
typedef struct { typedef struct {
TCGReg base; TCGReg base;
int index; int index;
@ -2051,18 +2068,7 @@ static void tcg_out_test_alignment(TCGContext *s, bool is_ld, TCGReg addrlo,
unsigned a_mask = (1 << a_bits) - 1; unsigned a_mask = (1 << a_bits) - 1;
TCGLabelQemuLdst *label; TCGLabelQemuLdst *label;
/* tcg_out_testi(s, addrlo, a_mask);
* We are expecting a_bits to max out at 7, so we can usually use testb.
* For i686, we have to use testl for %esi/%edi.
*/
if (a_mask <= 0xff && (TCG_TARGET_REG_BITS == 64 || addrlo < 4)) {
tcg_out_modrm(s, OPC_GRP3_Eb | P_REXB_RM, EXT3_TESTi, addrlo);
tcg_out8(s, a_mask);
} else {
tcg_out_modrm(s, OPC_GRP3_Ev, EXT3_TESTi, addrlo);
tcg_out32(s, a_mask);
}
/* jne slow_path */ /* jne slow_path */
tcg_out_opc(s, OPC_JCC_long + JCC_JNE, 0, 0, 0); tcg_out_opc(s, OPC_JCC_long + JCC_JNE, 0, 0, 0);