diff options
| -rw-r--r-- | target/arm/translate-a64.c | 66 |
1 files changed, 23 insertions, 43 deletions
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c index f49fe1de3a..4d28a27c3b 100644 --- a/target/arm/translate-a64.c +++ b/target/arm/translate-a64.c @@ -261,7 +261,7 @@ void gen_a64_set_pc_im(uint64_t val) /* Load the PC from a generic TCG variable. * * If address tagging is enabled via the TCR TBI bits, then loading - * an address into the PC will clear out any tag in the it: + * an address into the PC will clear out any tag in it: * + for EL2 and EL3 there is only one TBI bit, and if it is set * then the address is zero-extended, clearing bits [63:56] * + for EL0 and EL1, TBI0 controls addresses with bit 55 == 0 @@ -280,54 +280,34 @@ static void gen_a64_set_pc(DisasContext *s, TCGv_i64 src) int tbi = s->tbii; if (s->current_el <= 1) { - /* Test if NEITHER or BOTH TBI values are set. If so, no need to - * examine bit 55 of address, can just generate code. - * If mixed, then test via generated code - */ - if (tbi == 3) { - TCGv_i64 tmp_reg = tcg_temp_new_i64(); - /* Both bits set, sign extension from bit 55 into [63:56] will - * cover both cases - */ - tcg_gen_shli_i64(tmp_reg, src, 8); - tcg_gen_sari_i64(cpu_pc, tmp_reg, 8); - tcg_temp_free_i64(tmp_reg); - } else if (tbi == 0) { - /* Neither bit set, just load it as-is */ - tcg_gen_mov_i64(cpu_pc, src); - } else { - TCGv_i64 tcg_tmpval = tcg_temp_new_i64(); - TCGv_i64 tcg_bit55 = tcg_temp_new_i64(); - TCGv_i64 tcg_zero = tcg_const_i64(0); - - tcg_gen_andi_i64(tcg_bit55, src, (1ull << 55)); - - if (tbi == 1) { - /* tbi0==1, tbi1==0, so 0-fill upper byte if bit 55 = 0 */ - tcg_gen_andi_i64(tcg_tmpval, src, - 0x00FFFFFFFFFFFFFFull); - tcg_gen_movcond_i64(TCG_COND_EQ, cpu_pc, tcg_bit55, tcg_zero, - tcg_tmpval, src); - } else { - /* tbi0==0, tbi1==1, so 1-fill upper byte if bit 55 = 1 */ - tcg_gen_ori_i64(tcg_tmpval, src, - 0xFF00000000000000ull); - tcg_gen_movcond_i64(TCG_COND_NE, cpu_pc, tcg_bit55, tcg_zero, - tcg_tmpval, src); + if (tbi != 0) { + /* Sign-extend from bit 55. */ + tcg_gen_sextract_i64(cpu_pc, src, 0, 56); + + if (tbi != 3) { + TCGv_i64 tcg_zero = tcg_const_i64(0); + + /* + * The two TBI bits differ. + * If tbi0, then !tbi1: only use the extension if positive. + * if !tbi0, then tbi1: only use the extension if negative. + */ + tcg_gen_movcond_i64(tbi == 1 ? TCG_COND_GE : TCG_COND_LT, + cpu_pc, cpu_pc, tcg_zero, cpu_pc, src); + tcg_temp_free_i64(tcg_zero); } - tcg_temp_free_i64(tcg_zero); - tcg_temp_free_i64(tcg_bit55); - tcg_temp_free_i64(tcg_tmpval); + return; } - } else { /* EL > 1 */ + } else { if (tbi != 0) { /* Force tag byte to all zero */ - tcg_gen_andi_i64(cpu_pc, src, 0x00FFFFFFFFFFFFFFull); - } else { - /* Load unmodified address */ - tcg_gen_mov_i64(cpu_pc, src); + tcg_gen_extract_i64(cpu_pc, src, 0, 56); + return; } } + + /* Load unmodified address */ + tcg_gen_mov_i64(cpu_pc, src); } typedef struct DisasCompare64 { |