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| author | Richard Henderson <richard.henderson@linaro.org> | 2017-09-04 15:21:56 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2017-09-04 17:13:53 +0100 |
| commit | 3e4d91b94ce400326fae0850578d9e9f30a71adb (patch) | |
| tree | 9521c8a351f96409beb5fea325d9bb207b7acb7b | |
| parent | f58f25599b72c7479e6a1ff67c7f671823aa14da (diff) | |
| download | focaccia-qemu-3e4d91b94ce400326fae0850578d9e9f30a71adb.tar.gz focaccia-qemu-3e4d91b94ce400326fae0850578d9e9f30a71adb.zip | |
target/arm: Fix aa64 ldp register writeback
For "ldp x0, x1, [x0]", if the second load is on a second page and the second page is unmapped, the exception would be raised with x0 already modified. This means the instruction couldn't be restarted. Cc: qemu-arm@nongnu.org Cc: qemu-stable@nongnu.org Reported-by: Andrew <andrew@fubar.geek.nz> Signed-off-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20170825224833.4463-1-richard.henderson@linaro.org Fixes: https://bugs.launchpad.net/qemu/+bug/1713066 Signed-off-by: Richard Henderson <richard.henderson@linaro.org> [PMM: tweaked comment format] Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
| -rw-r--r-- | target/arm/translate-a64.c | 29 |
1 files changed, 17 insertions, 12 deletions
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c index 2200e25be0..cb44632d16 100644 --- a/target/arm/translate-a64.c +++ b/target/arm/translate-a64.c @@ -2217,29 +2217,34 @@ static void disas_ldst_pair(DisasContext *s, uint32_t insn) } else { do_fp_st(s, rt, tcg_addr, size); } - } else { - TCGv_i64 tcg_rt = cpu_reg(s, rt); - if (is_load) { - do_gpr_ld(s, tcg_rt, tcg_addr, size, is_signed, false, - false, 0, false, false); - } else { - do_gpr_st(s, tcg_rt, tcg_addr, size, - false, 0, false, false); - } - } - tcg_gen_addi_i64(tcg_addr, tcg_addr, 1 << size); - if (is_vector) { + tcg_gen_addi_i64(tcg_addr, tcg_addr, 1 << size); if (is_load) { do_fp_ld(s, rt2, tcg_addr, size); } else { do_fp_st(s, rt2, tcg_addr, size); } } else { + TCGv_i64 tcg_rt = cpu_reg(s, rt); TCGv_i64 tcg_rt2 = cpu_reg(s, rt2); + if (is_load) { + TCGv_i64 tmp = tcg_temp_new_i64(); + + /* Do not modify tcg_rt before recognizing any exception + * from the second load. + */ + do_gpr_ld(s, tmp, tcg_addr, size, is_signed, false, + false, 0, false, false); + tcg_gen_addi_i64(tcg_addr, tcg_addr, 1 << size); do_gpr_ld(s, tcg_rt2, tcg_addr, size, is_signed, false, false, 0, false, false); + + tcg_gen_mov_i64(tcg_rt, tmp); + tcg_temp_free_i64(tmp); } else { + do_gpr_st(s, tcg_rt, tcg_addr, size, + false, 0, false, false); + tcg_gen_addi_i64(tcg_addr, tcg_addr, 1 << size); do_gpr_st(s, tcg_rt2, tcg_addr, size, false, 0, false, false); } |