Patchwork target-sparc: fix udiv(cc) and sdiv(cc)

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Submitter Aurelien Jarno
Date Dec. 25, 2010, 10:25 p.m.
Message ID <1293315947-8961-1-git-send-email-aurelien@aurel32.net>
Download mbox | patch
Permalink /patch/76706/
State New
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Comments

Aurelien Jarno - Dec. 25, 2010, 10:25 p.m.
Since commit 5a4bb580cdb10b066f9fd67658b31cac4a4ea5e5, Xorg crashes on
a Debian Etch image. The commit itself is fine, but it triggers a bug
due to wrong computation of flags for udiv(cc) and sdiv(cc).

This patch only compute cc_src2 for the cc version of udiv/sdiv. It
also moves the update of cc_dst and cc_op to the helper, as it is
faster doing it here when there is already an helper.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
---
 target-sparc/helper.h    |    2 +
 target-sparc/op_helper.c |   54 +++++++++++++++++++++++++++++++++++----------
 target-sparc/translate.c |   12 +++++-----
 3 files changed, 50 insertions(+), 18 deletions(-)
Blue Swirl - Dec. 28, 2010, 9:21 p.m.
Thanks, applied.

On Sat, Dec 25, 2010 at 10:25 PM, Aurelien Jarno <aurelien@aurel32.net> wrote:
> Since commit 5a4bb580cdb10b066f9fd67658b31cac4a4ea5e5, Xorg crashes on
> a Debian Etch image. The commit itself is fine, but it triggers a bug
> due to wrong computation of flags for udiv(cc) and sdiv(cc).
>
> This patch only compute cc_src2 for the cc version of udiv/sdiv. It
> also moves the update of cc_dst and cc_op to the helper, as it is
> faster doing it here when there is already an helper.
>
> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
> ---
>  target-sparc/helper.h    |    2 +
>  target-sparc/op_helper.c |   54 +++++++++++++++++++++++++++++++++++----------
>  target-sparc/translate.c |   12 +++++-----
>  3 files changed, 50 insertions(+), 18 deletions(-)
>
> diff --git a/target-sparc/helper.h b/target-sparc/helper.h
> index 6f103e7..e6d82f9 100644
> --- a/target-sparc/helper.h
> +++ b/target-sparc/helper.h
> @@ -37,7 +37,9 @@ DEF_HELPER_0(save, void)
>  DEF_HELPER_0(restore, void)
>  DEF_HELPER_1(flush, void, tl)
>  DEF_HELPER_2(udiv, tl, tl, tl)
> +DEF_HELPER_2(udiv_cc, tl, tl, tl)
>  DEF_HELPER_2(sdiv, tl, tl, tl)
> +DEF_HELPER_2(sdiv_cc, tl, tl, tl)
>  DEF_HELPER_2(stdf, void, tl, int)
>  DEF_HELPER_2(lddf, void, tl, int)
>  DEF_HELPER_2(ldqf, void, tl, int)
> diff --git a/target-sparc/op_helper.c b/target-sparc/op_helper.c
> index 4f753ba..58f9f82 100644
> --- a/target-sparc/op_helper.c
> +++ b/target-sparc/op_helper.c
> @@ -3300,8 +3300,9 @@ void helper_rett(void)
>  }
>  #endif
>
> -target_ulong helper_udiv(target_ulong a, target_ulong b)
> +static target_ulong helper_udiv_common(target_ulong a, target_ulong b, int cc)
>  {
> +    int overflow = 0;
>     uint64_t x0;
>     uint32_t x1;
>
> @@ -3314,16 +3315,31 @@ target_ulong helper_udiv(target_ulong a, target_ulong b)
>
>     x0 = x0 / x1;
>     if (x0 > 0xffffffff) {
> -        env->cc_src2 = 1;
> -        return 0xffffffff;
> -    } else {
> -        env->cc_src2 = 0;
> -        return x0;
> +        x0 = 0xffffffff;
> +        overflow = 1;
> +    }
> +
> +    if (cc) {
> +        env->cc_dst = x0;
> +        env->cc_src2 = overflow;
> +        env->cc_op = CC_OP_DIV;
>     }
> +    return x0;
>  }
>
> -target_ulong helper_sdiv(target_ulong a, target_ulong b)
> +target_ulong helper_udiv(target_ulong a, target_ulong b)
> +{
> +    return helper_udiv_common(a, b, 0);
> +}
> +
> +target_ulong helper_udiv_cc(target_ulong a, target_ulong b)
> +{
> +    return helper_udiv_common(a, b, 1);
> +}
> +
> +static target_ulong helper_sdiv_common(target_ulong a, target_ulong b, int cc)
>  {
> +    int overflow = 0;
>     int64_t x0;
>     int32_t x1;
>
> @@ -3336,12 +3352,26 @@ target_ulong helper_sdiv(target_ulong a, target_ulong b)
>
>     x0 = x0 / x1;
>     if ((int32_t) x0 != x0) {
> -        env->cc_src2 = 1;
> -        return x0 < 0? 0x80000000: 0x7fffffff;
> -    } else {
> -        env->cc_src2 = 0;
> -        return x0;
> +        x0 = x0 < 0 ? 0x80000000: 0x7fffffff;
> +        overflow = 1;
> +    }
> +
> +    if (cc) {
> +        env->cc_dst = x0;
> +        env->cc_src2 = overflow;
> +        env->cc_op = CC_OP_DIV;
>     }
> +    return x0;
> +}
> +
> +target_ulong helper_sdiv(target_ulong a, target_ulong b)
> +{
> +    return helper_sdiv_common(a, b, 0);
> +}
> +
> +target_ulong helper_sdiv_cc(target_ulong a, target_ulong b)
> +{
> +    return helper_sdiv_common(a, b, 1);
>  }
>
>  void helper_stdf(target_ulong addr, int mem_idx)
> diff --git a/target-sparc/translate.c b/target-sparc/translate.c
> index 23f9519..21c5675 100644
> --- a/target-sparc/translate.c
> +++ b/target-sparc/translate.c
> @@ -3162,20 +3162,20 @@ static void disas_sparc_insn(DisasContext * dc)
>  #endif
>                     case 0xe: /* udiv */
>                         CHECK_IU_FEATURE(dc, DIV);
> -                        gen_helper_udiv(cpu_dst, cpu_src1, cpu_src2);
>                         if (xop & 0x10) {
> -                            tcg_gen_mov_tl(cpu_cc_dst, cpu_dst);
> -                            tcg_gen_movi_i32(cpu_cc_op, CC_OP_DIV);
> +                            gen_helper_udiv_cc(cpu_dst, cpu_src1, cpu_src2);
>                             dc->cc_op = CC_OP_DIV;
> +                        } else {
> +                            gen_helper_udiv(cpu_dst, cpu_src1, cpu_src2);
>                         }
>                         break;
>                     case 0xf: /* sdiv */
>                         CHECK_IU_FEATURE(dc, DIV);
> -                        gen_helper_sdiv(cpu_dst, cpu_src1, cpu_src2);
>                         if (xop & 0x10) {
> -                            tcg_gen_mov_tl(cpu_cc_dst, cpu_dst);
> -                            tcg_gen_movi_i32(cpu_cc_op, CC_OP_DIV);
> +                            gen_helper_sdiv_cc(cpu_dst, cpu_src1, cpu_src2);
>                             dc->cc_op = CC_OP_DIV;
> +                        } else {
> +                            gen_helper_sdiv(cpu_dst, cpu_src1, cpu_src2);
>                         }
>                         break;
>                     default:
> --
> 1.7.2.3
>
>

Patch

diff --git a/target-sparc/helper.h b/target-sparc/helper.h
index 6f103e7..e6d82f9 100644
--- a/target-sparc/helper.h
+++ b/target-sparc/helper.h
@@ -37,7 +37,9 @@  DEF_HELPER_0(save, void)
 DEF_HELPER_0(restore, void)
 DEF_HELPER_1(flush, void, tl)
 DEF_HELPER_2(udiv, tl, tl, tl)
+DEF_HELPER_2(udiv_cc, tl, tl, tl)
 DEF_HELPER_2(sdiv, tl, tl, tl)
+DEF_HELPER_2(sdiv_cc, tl, tl, tl)
 DEF_HELPER_2(stdf, void, tl, int)
 DEF_HELPER_2(lddf, void, tl, int)
 DEF_HELPER_2(ldqf, void, tl, int)
diff --git a/target-sparc/op_helper.c b/target-sparc/op_helper.c
index 4f753ba..58f9f82 100644
--- a/target-sparc/op_helper.c
+++ b/target-sparc/op_helper.c
@@ -3300,8 +3300,9 @@  void helper_rett(void)
 }
 #endif
 
-target_ulong helper_udiv(target_ulong a, target_ulong b)
+static target_ulong helper_udiv_common(target_ulong a, target_ulong b, int cc)
 {
+    int overflow = 0;
     uint64_t x0;
     uint32_t x1;
 
@@ -3314,16 +3315,31 @@  target_ulong helper_udiv(target_ulong a, target_ulong b)
 
     x0 = x0 / x1;
     if (x0 > 0xffffffff) {
-        env->cc_src2 = 1;
-        return 0xffffffff;
-    } else {
-        env->cc_src2 = 0;
-        return x0;
+        x0 = 0xffffffff;
+        overflow = 1;
+    }
+
+    if (cc) {
+        env->cc_dst = x0;
+        env->cc_src2 = overflow;
+        env->cc_op = CC_OP_DIV;
     }
+    return x0;
 }
 
-target_ulong helper_sdiv(target_ulong a, target_ulong b)
+target_ulong helper_udiv(target_ulong a, target_ulong b)
+{
+    return helper_udiv_common(a, b, 0);
+}
+
+target_ulong helper_udiv_cc(target_ulong a, target_ulong b)
+{
+    return helper_udiv_common(a, b, 1);
+}
+
+static target_ulong helper_sdiv_common(target_ulong a, target_ulong b, int cc)
 {
+    int overflow = 0;
     int64_t x0;
     int32_t x1;
 
@@ -3336,12 +3352,26 @@  target_ulong helper_sdiv(target_ulong a, target_ulong b)
 
     x0 = x0 / x1;
     if ((int32_t) x0 != x0) {
-        env->cc_src2 = 1;
-        return x0 < 0? 0x80000000: 0x7fffffff;
-    } else {
-        env->cc_src2 = 0;
-        return x0;
+        x0 = x0 < 0 ? 0x80000000: 0x7fffffff;
+        overflow = 1;
+    }
+
+    if (cc) {
+        env->cc_dst = x0;
+        env->cc_src2 = overflow;
+        env->cc_op = CC_OP_DIV;
     }
+    return x0;
+}
+
+target_ulong helper_sdiv(target_ulong a, target_ulong b)
+{
+    return helper_sdiv_common(a, b, 0);
+}
+
+target_ulong helper_sdiv_cc(target_ulong a, target_ulong b)
+{
+    return helper_sdiv_common(a, b, 1);
 }
 
 void helper_stdf(target_ulong addr, int mem_idx)
diff --git a/target-sparc/translate.c b/target-sparc/translate.c
index 23f9519..21c5675 100644
--- a/target-sparc/translate.c
+++ b/target-sparc/translate.c
@@ -3162,20 +3162,20 @@  static void disas_sparc_insn(DisasContext * dc)
 #endif
                     case 0xe: /* udiv */
                         CHECK_IU_FEATURE(dc, DIV);
-                        gen_helper_udiv(cpu_dst, cpu_src1, cpu_src2);
                         if (xop & 0x10) {
-                            tcg_gen_mov_tl(cpu_cc_dst, cpu_dst);
-                            tcg_gen_movi_i32(cpu_cc_op, CC_OP_DIV);
+                            gen_helper_udiv_cc(cpu_dst, cpu_src1, cpu_src2);
                             dc->cc_op = CC_OP_DIV;
+                        } else {
+                            gen_helper_udiv(cpu_dst, cpu_src1, cpu_src2);
                         }
                         break;
                     case 0xf: /* sdiv */
                         CHECK_IU_FEATURE(dc, DIV);
-                        gen_helper_sdiv(cpu_dst, cpu_src1, cpu_src2);
                         if (xop & 0x10) {
-                            tcg_gen_mov_tl(cpu_cc_dst, cpu_dst);
-                            tcg_gen_movi_i32(cpu_cc_op, CC_OP_DIV);
+                            gen_helper_sdiv_cc(cpu_dst, cpu_src1, cpu_src2);
                             dc->cc_op = CC_OP_DIV;
+                        } else {
+                            gen_helper_sdiv(cpu_dst, cpu_src1, cpu_src2);
                         }
                         break;
                     default: