diff mbox series

[v2,56/68] target/arm: Convert T16, Change processor state

Message ID 20190819213755.26175-57-richard.henderson@linaro.org
State Superseded
Headers show
Series target/arm: Convert aa32 base isa to decodetree | expand

Commit Message

Richard Henderson Aug. 19, 2019, 9:37 p.m. UTC
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

---
 target/arm/translate.c | 85 ++++++++++++++++++++----------------------
 target/arm/t16.decode  | 12 ++++++
 2 files changed, 52 insertions(+), 45 deletions(-)

-- 
2.17.1

Comments

Peter Maydell Aug. 26, 2019, 7:25 p.m. UTC | #1
On Mon, 19 Aug 2019 at 22:39, Richard Henderson
<richard.henderson@linaro.org> wrote:
>

> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

> ---

>  target/arm/translate.c | 85 ++++++++++++++++++++----------------------

>  target/arm/t16.decode  | 12 ++++++

>  2 files changed, 52 insertions(+), 45 deletions(-)

>

> diff --git a/target/arm/translate.c b/target/arm/translate.c

> index 414c562fb3..368f0ab147 100644

> --- a/target/arm/translate.c

> +++ b/target/arm/translate.c

> @@ -7474,6 +7474,11 @@ static int negate(DisasContext *s, int x)

>      return -x;

>  }

>

> +static int plus_2(DisasContext *s, int x)

> +{

> +    return x + 2;

> +}

> +

>  static int times_2(DisasContext *s, int x)

>  {

>      return x * 2;

> @@ -10152,6 +10157,9 @@ static bool trans_CPS(DisasContext *s, arg_CPS *a)

>  {

>      uint32_t mask, val;

>

> +    if (ENABLE_ARCH_6 && arm_dc_feature(s, ARM_FEATURE_M)) {

> +        return false;

> +    }


I don't think this condition is quite right. We want to
do two things:
 (1) this is the A/R-profile CPS, so it shouldn't
be decoded for any ARM_FEATURE_M CPU
 (2) for A/R-profile, all the CPS instructions are v6-or-better

(All M-profile CPUs are at v6-or-better, which is why the
legacy decoder gets away with doing its ARCH(6) check
up front rather than only in the A/R-profile arm of its
if statement.)

>      if (IS_USER(s)) {>          /* Implemented as NOP in user mode.  */

>          return true;

> @@ -10182,6 +10190,36 @@ static bool trans_CPS(DisasContext *s, arg_CPS *a)

>      return true;

>  }

>

> +static bool trans_CPS_v6m(DisasContext *s, arg_CPS_v6m *a)

> +{

> +    TCGv_i32 tmp, addr;

> +

> +    if (!(ENABLE_ARCH_6 && arm_dc_feature(s, ARM_FEATURE_M))) {

> +        return false;

> +    }


Similarly, this one need not check ENABLE_ARCH_6.
That is, this is the generic M-profile CPS, it's
not specific to v6M, and FEATURE_M always implies
ARCH_6 anyway. Usually we name M-profile specific
functions _v7m, not _v6m, for mostly historical
reasons relating to our having implemented v7m first,
so maybe we should follow that here. I have made
a bit of an inconsistent hash of this with the v8M
support, where sometimes I use _v8m because the
function is only in v8M and not v7M, and sometimes
_v7m because it's an M-profile function even if it
happens that it only kicks in or is called for
v8M CPUs. But we do not curretly have any functions
with a _v6m suffix so we should probably go with _v7m here.

> +    if (IS_USER(s)) {

> +        /* Implemented as NOP in user mode.  */

> +        return true;

> +    }

> +

> +    tmp = tcg_const_i32(a->im);

> +    /* FAULTMASK */

> +    if (a->F) {

> +        addr = tcg_const_i32(19);

> +        gen_helper_v7m_msr(cpu_env, addr, tmp);

> +        tcg_temp_free_i32(addr);

> +    }

> +    /* PRIMASK */

> +    if (a->I) {

> +        addr = tcg_const_i32(16);

> +        gen_helper_v7m_msr(cpu_env, addr, tmp);

> +        tcg_temp_free_i32(addr);

> +    }

> +    tcg_temp_free_i32(tmp);

> +    gen_lookup_tb(s);

> +    return true;

> +}


thanks
-- PMM
diff mbox series

Patch

diff --git a/target/arm/translate.c b/target/arm/translate.c
index 414c562fb3..368f0ab147 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -7474,6 +7474,11 @@  static int negate(DisasContext *s, int x)
     return -x;
 }
 
+static int plus_2(DisasContext *s, int x)
+{
+    return x + 2;
+}
+
 static int times_2(DisasContext *s, int x)
 {
     return x * 2;
@@ -10152,6 +10157,9 @@  static bool trans_CPS(DisasContext *s, arg_CPS *a)
 {
     uint32_t mask, val;
 
+    if (ENABLE_ARCH_6 && arm_dc_feature(s, ARM_FEATURE_M)) {
+        return false;
+    }
     if (IS_USER(s)) {
         /* Implemented as NOP in user mode.  */
         return true;
@@ -10182,6 +10190,36 @@  static bool trans_CPS(DisasContext *s, arg_CPS *a)
     return true;
 }
 
+static bool trans_CPS_v6m(DisasContext *s, arg_CPS_v6m *a)
+{
+    TCGv_i32 tmp, addr;
+
+    if (!(ENABLE_ARCH_6 && arm_dc_feature(s, ARM_FEATURE_M))) {
+        return false;
+    }
+    if (IS_USER(s)) {
+        /* Implemented as NOP in user mode.  */
+        return true;
+    }
+
+    tmp = tcg_const_i32(a->im);
+    /* FAULTMASK */
+    if (a->F) {
+        addr = tcg_const_i32(19);
+        gen_helper_v7m_msr(cpu_env, addr, tmp);
+        tcg_temp_free_i32(addr);
+    }
+    /* PRIMASK */
+    if (a->I) {
+        addr = tcg_const_i32(16);
+        gen_helper_v7m_msr(cpu_env, addr, tmp);
+        tcg_temp_free_i32(addr);
+    }
+    tcg_temp_free_i32(tmp);
+    gen_lookup_tb(s);
+    return true;
+}
+
 /*
  * Clear-Exclusive, Barriers
  */
@@ -10783,51 +10821,8 @@  static void disas_thumb_insn(DisasContext *s, uint32_t insn)
             break;
         }
 
-        case 6:
-            switch ((insn >> 5) & 7) {
-            case 2:
-                /* setend */
-                ARCH(6);
-                if (((insn >> 3) & 1) != !!(s->be_data == MO_BE)) {
-                    gen_helper_setend(cpu_env);
-                    s->base.is_jmp = DISAS_UPDATE;
-                }
-                break;
-            case 3:
-                /* cps */
-                ARCH(6);
-                if (IS_USER(s)) {
-                    break;
-                }
-                if (arm_dc_feature(s, ARM_FEATURE_M)) {
-                    tmp = tcg_const_i32((insn & (1 << 4)) != 0);
-                    /* FAULTMASK */
-                    if (insn & 1) {
-                        addr = tcg_const_i32(19);
-                        gen_helper_v7m_msr(cpu_env, addr, tmp);
-                        tcg_temp_free_i32(addr);
-                    }
-                    /* PRIMASK */
-                    if (insn & 2) {
-                        addr = tcg_const_i32(16);
-                        gen_helper_v7m_msr(cpu_env, addr, tmp);
-                        tcg_temp_free_i32(addr);
-                    }
-                    tcg_temp_free_i32(tmp);
-                    gen_lookup_tb(s);
-                } else {
-                    if (insn & (1 << 4)) {
-                        shift = CPSR_A | CPSR_I | CPSR_F;
-                    } else {
-                        shift = 0;
-                    }
-                    gen_set_psr_im(s, ((insn & 7) << 6), 0, shift);
-                }
-                break;
-            default:
-                goto undef;
-            }
-            break;
+        case 6: /* setend, cps; in decodetree */
+            goto illegal_op;
 
         default:
             goto undef;
diff --git a/target/arm/t16.decode b/target/arm/t16.decode
index b5b5086e8a..3bf1a31731 100644
--- a/target/arm/t16.decode
+++ b/target/arm/t16.decode
@@ -29,6 +29,8 @@ 
 &ldst_rr         !extern p w u rn rt rm shimm shtype
 &ldst_ri         !extern p w u rn rt imm
 &ldst_block      !extern rn i b u w list
+&setend          !extern E
+&cps             !extern mode imod M A I F
 
 # Set S if the instruction is outside of an IT block.
 %s               !function=t16_setflags
@@ -183,3 +185,13 @@  SXTAH           1011 0010 00 ... ...            @extend
 SXTAB           1011 0010 01 ... ...            @extend
 UXTAH           1011 0010 10 ... ...            @extend
 UXTAB           1011 0010 11 ... ...            @extend
+
+# Change processor state
+
+%imod           4:1 !function=plus_2
+
+SETEND          1011 0110 010 1 E:1 000         &setend
+{
+  CPS_v6m       1011 0110 011 im:1 00 I:1 F:1
+  CPS           1011 0110 011 . 0 A:1 I:1 F:1   &cps mode=0 M=0 %imod
+}