target/arm: Convert T16, Change processor state

Add a check for ARMv6 in trans_CPS.  We had this correct in
the T16 path, but had previously forgotten the check on the
A32 and T32 paths.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20190904193059.26202-58-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 50 insertions, 46 deletions

diff --git a/target/arm/t16.decode b/target/arm/t16.decode
index b5b5086e8a..032902a1f4 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           1011 0110 011 . 0 A:1 I:1 F:1   &cps mode=0 M=0 %imod
+  CPS_v7m       1011 0110 011 im:1 00 I:1 F:1
+}
diff --git a/target/arm/translate.c b/target/arm/translate.c
index 09c05de320..ce394ddb00 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -7496,6 +7496,11 @@ 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;
@@ -10268,7 +10273,7 @@ static bool trans_CPS(DisasContext *s, arg_CPS *a)
 {
     uint32_t mask, val;
 
-    if (arm_dc_feature(s, ARM_FEATURE_M)) {
+    if (!ENABLE_ARCH_6 || arm_dc_feature(s, ARM_FEATURE_M)) {
         return false;
     }
     if (IS_USER(s)) {
@@ -10302,6 +10307,36 @@ static bool trans_CPS(DisasContext *s, arg_CPS *a)
     return true;
 }
 
+static bool trans_CPS_v7m(DisasContext *s, arg_CPS_v7m *a)
+{
+    TCGv_i32 tmp, addr;
+
+    if (!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
  */
@@ -10908,51 +10943,8 @@ 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;