From 4c97f5b2f0fa9b37f9ff497f15411d809e6fd098 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 4 Sep 2019 12:30:06 -0700 Subject: [PATCH] target/arm: Convert CLZ Document our choice about the T32 CONSTRAINED UNPREDICTABLE behaviour. This matches the undocumented choice made by the legacy decoder. Reviewed-by: Peter Maydell Signed-off-by: Richard Henderson Message-id: 20190904193059.26202-17-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- target/arm/a32.decode | 4 ++++ target/arm/t32.decode | 5 +++++ target/arm/translate.c | 31 +++++++++++++++---------------- 3 files changed, 24 insertions(+), 16 deletions(-) diff --git a/target/arm/a32.decode b/target/arm/a32.decode index 6cb9c16e2f..182f2b6725 100644 --- a/target/arm/a32.decode +++ b/target/arm/a32.decode @@ -29,6 +29,7 @@ &s_rrrr s rd rn rm ra &rrrr rd rn rm ra &rrr rd rn rm +&rr rd rm &r rm &msr_reg rn r mask &mrs_reg rd r @@ -197,6 +198,7 @@ CRC32CW .... 0001 0100 .... .... 0010 0100 .... @rndm %sysm 8:1 16:4 @rm ---- .... .... .... .... .... .... rm:4 &r +@rdm ---- .... .... .... rd:4 .... .... rm:4 &rr MRS_bank ---- 0001 0 r:1 00 .... rd:4 001. 0000 0000 &mrs_bank %sysm MSR_bank ---- 0001 0 r:1 10 .... 1111 001. 0000 rn:4 &msr_bank %sysm @@ -207,3 +209,5 @@ MSR_reg ---- 0001 0 r:1 10 mask:4 1111 0000 0000 rn:4 &msr_reg BX .... 0001 0010 1111 1111 1111 0001 .... @rm BXJ .... 0001 0010 1111 1111 1111 0010 .... @rm BLX_r .... 0001 0010 1111 1111 1111 0011 .... @rm + +CLZ .... 0001 0110 1111 .... 1111 0001 .... @rdm diff --git a/target/arm/t32.decode b/target/arm/t32.decode index 337706ebbe..67724efe4b 100644 --- a/target/arm/t32.decode +++ b/target/arm/t32.decode @@ -26,6 +26,7 @@ &s_rrrr !extern s rd rn rm ra &rrrr !extern rd rn rm ra &rrr !extern rd rn rm +&rr !extern rd rm &r !extern rm &msr_reg !extern rn r mask &mrs_reg !extern rd r @@ -126,6 +127,7 @@ RSB_rri 1111 0.0 1110 . .... 0 ... .... ........ @s_rri_rot @rnadm .... .... .... rn:4 ra:4 rd:4 .... rm:4 &rrrr @rn0dm .... .... .... rn:4 .... rd:4 .... rm:4 &rrrr ra=0 @rndm .... .... .... rn:4 .... rd:4 .... rm:4 &rrr +@rdm .... .... .... .... .... rd:4 .... rm:4 &rr { MUL 1111 1011 0000 .... 1111 .... 0000 .... @s0_rn0dm @@ -180,6 +182,9 @@ CRC32CB 1111 1010 1101 .... 1111 .... 1000 .... @rndm CRC32CH 1111 1010 1101 .... 1111 .... 1001 .... @rndm CRC32CW 1111 1010 1101 .... 1111 .... 1010 .... @rndm +# Note rn != rm is CONSTRAINED UNPREDICTABLE; we choose to ignore rn. +CLZ 1111 1010 1011 ---- 1111 .... 1000 .... @rdm + # Branches and miscellaneous control %msr_sysm 4:1 8:4 diff --git a/target/arm/translate.c b/target/arm/translate.c index 386a460bf5..7de6949db3 100644 --- a/target/arm/translate.c +++ b/target/arm/translate.c @@ -8490,6 +8490,19 @@ static bool trans_BLX_r(DisasContext *s, arg_BLX_r *a) return true; } +static bool trans_CLZ(DisasContext *s, arg_CLZ *a) +{ + TCGv_i32 tmp; + + if (!ENABLE_ARCH_5) { + return false; + } + tmp = load_reg(s, a->rm); + tcg_gen_clzi_i32(tmp, tmp, 32); + store_reg(s, a->rd, tmp); + return true; +} + /* * Legacy decoder. */ @@ -8778,18 +8791,7 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn) /* MSR/MRS (banked/register) */ /* All done in decodetree. Illegal ops already signalled. */ g_assert_not_reached(); - case 0x1: - if (op1 == 3) { - /* clz */ - ARCH(5); - rd = (insn >> 12) & 0xf; - tmp = load_reg(s, rm); - tcg_gen_clzi_i32(tmp, tmp, 32); - store_reg(s, rd, tmp); - } else { - goto illegal_op; - } - break; + case 0x1: /* bx, clz */ case 0x2: /* bxj */ case 0x3: /* blx */ case 0x4: /* crc32 */ @@ -10236,13 +10238,13 @@ static void disas_thumb2_insn(DisasContext *s, uint32_t insn) case 0x08: /* rev */ case 0x09: /* rev16 */ case 0x0b: /* revsh */ - case 0x18: /* clz */ break; case 0x10: /* sel */ if (!arm_dc_feature(s, ARM_FEATURE_THUMB_DSP)) { goto illegal_op; } break; + case 0x18: /* clz, in decodetree */ case 0x20: /* crc32/crc32c, in decodetree */ case 0x21: case 0x22: @@ -10275,9 +10277,6 @@ static void disas_thumb2_insn(DisasContext *s, uint32_t insn) tcg_temp_free_i32(tmp3); tcg_temp_free_i32(tmp2); break; - case 0x18: /* clz */ - tcg_gen_clzi_i32(tmp, tmp, 32); - break; default: g_assert_not_reached(); }