target/arm: Convert CPS (privileged)

Backports commit 52f83b9c68bdde8d3da5f49292d3561bd474651d from qemu

qemu/target/arm/a32-uncond.decode

@@ -35,9 +35,12 @@ BLX_i            1111 101 . ........................          &i imm=%imm24h
 
 &rfe             rn w pu
 &srs             mode w pu
+&cps             mode imod M A I F
 
 RFE              1111 100 pu:2 0 w:1 1 rn:4 0000 1010 0000 0000   &rfe
 SRS              1111 100 pu:2 1 w:1 0 1101 0000 0101 000 mode:5  &srs
+CPS              1111 0001 0000 imod:2 M:1 0 0000 000 A:1 I:1 F:1 0 mode:5 \
+                 &cps
 
 # Clear-Exclusive, Barriers
 

qemu/target/arm/t32.decode

@@ -44,6 +44,7 @@
 &bfi             !extern rd rn lsb msb
 &sat             !extern rd rn satimm imm sh
 &pkh             !extern rd rn rm imm tb
+&cps             !extern mode imod M A I F
 
 # Data-processing (register)
 
@@ -306,6 +307,10 @@ CLZ              1111 1010 1011 ---- 1111 .... 1000 ....      @rdm
       NOP        1111 0011 1010 1111 1000 0000 ---- ----
     }
 
+    # If imod == '00' && M == '0' then SEE "Hint instructions", above.
+    CPS          1111 0011 1010 1111 1000 0 imod:2 M:1 A:1 I:1 F:1 mode:5 \
+                 &cps
+
     # Miscellaneous control
     {
       CLREX      1111 0011 1011 1111 1000 1111 0010 1111

qemu/target/arm/translate.c

@@ -10541,6 +10541,44 @@ static bool trans_SB(DisasContext *s, arg_SB *a)
     return true;
 }
 
+static bool trans_CPS(DisasContext *s, arg_CPS *a)
+{
+    uint32_t mask, val;
+
+    if (arm_dc_feature(s, ARM_FEATURE_M)) {
+        return false;
+    }
+    if (IS_USER(s)) {
+        /* Implemented as NOP in user mode.  */
+        return true;
+    }
+    /* TODO: There are quite a lot of UNPREDICTABLE argument combinations. */
+
+    mask = val = 0;
+    if (a->imod & 2) {
+        if (a->A) {
+            mask |= CPSR_A;
+        }
+        if (a->I) {
+            mask |= CPSR_I;
+        }
+        if (a->F) {
+            mask |= CPSR_F;
+        }
+        if (a->imod & 1) {
+            val |= mask;
+        }
+    }
+    if (a->M) {
+        mask |= CPSR_M;
+        val |= a->mode;
+    }
+    if (mask) {
+        gen_set_psr_im(s, mask, 0, val);
+    }
+    return true;
+}
+
 /*
  * Legacy decoder.
  */
@@ -10669,31 +10707,6 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn)
             ARCH(5TE);
         } else if ((insn & 0x0f000010) == 0x0e000010) {
             /* Additional coprocessor register transfer.  */
-        } else if ((insn & 0x0ff10020) == 0x01000000) {
-            uint32_t mask;
-            uint32_t val;
-            /* cps (privileged) */
-            if (IS_USER(s))
-                return;
-            mask = val = 0;
-            if (insn & (1 << 19)) {
-                if (insn & (1 << 8))
-                    mask |= CPSR_A;
-                if (insn & (1 << 7))
-                    mask |= CPSR_I;
-                if (insn & (1 << 6))
-                    mask |= CPSR_F;
-                if (insn & (1 << 18))
-                    val |= mask;
-            }
-            if (insn & (1 << 17)) {
-                mask |= CPSR_M;
-                val |= (insn & 0x1f);
-            }
-            if (mask) {
-                gen_set_psr_im(s, mask, 0, val);
-            }
-            return;
         }
         goto illegal_op;
     }
@@ -10805,7 +10818,6 @@ static bool thumb_insn_is_16bit(DisasContext *s, uint32_t pc, uint32_t insn)
 static void disas_thumb2_insn(DisasContext *s, uint32_t insn)
 {
     TCGContext *tcg_ctx = s->uc->tcg_ctx;
-    uint32_t imm, offset;
     uint32_t rd, rn, rm, rs;
     TCGv_i32 tmp;
     TCGv_i32 addr;
@@ -11082,31 +11094,8 @@ static void disas_thumb2_insn(DisasContext *s, uint32_t insn)
                     case 0: /* msr cpsr, in decodetree  */
                     case 1: /* msr spsr, in decodetree  */
                         goto illegal_op;
-                    case 2: /* cps, nop-hint.  */
+                    case 2: /* cps, nop-hint, in decodetree */
-                        /* nop hints in decodetree */
+                        goto illegal_op;
-                        /* Implemented as NOP in user mode.  */
-                        if (IS_USER(s))
-                            break;
-                        offset = 0;
-                        imm = 0;
-                        if (insn & (1 << 10)) {
-                            if (insn & (1 << 7))
-                                offset |= CPSR_A;
-                            if (insn & (1 << 6))
-                                offset |= CPSR_I;
-                            if (insn & (1 << 5))
-                                offset |= CPSR_F;
-                            if (insn & (1 << 9))
-                                imm = CPSR_A | CPSR_I | CPSR_F;
-                        }
-                        if (insn & (1 << 8)) {
-                            offset |= 0x1f;
-                            imm |= (insn & 0x1f);
-                        }
-                        if (offset) {
-                            gen_set_psr_im(s, offset, 0, imm);
-                        }
-                        break;
                     case 3: /* Special control operations, in decodetree */
                     case 4: /* bxj, in decodetree */
                         goto illegal_op;