target/arm: Convert MOVW, MOVT

Backports commit 8f4451274b7010c1f50e0baa5bb608f19f02b90f from qemu

qemu/target/arm/a32.decode

@@ -73,6 +73,12 @@ MOV_rxri         .... 000 1101 . 0000 .... ..... .. 0 ....    @s_rxr_shi
 BIC_rrri         .... 000 1110 . .... .... ..... .. 0 ....    @s_rrr_shi
 MVN_rxri         .... 000 1111 . 0000 .... ..... .. 0 ....    @s_rxr_shi
 
+%imm16           16:4 0:12
+@mov16           ---- .... .... .... rd:4 ............        &ri imm=%imm16
+
+MOVW             .... 0011 0000 .... .... ............        @mov16
+MOVT             .... 0011 0100 .... .... ............        @mov16
+
 # Data-processing (register-shifted register)
 
 @s_rrr_shr       ---- ... .... s:1 rn:4 rd:4 rs:4 . shty:2 . rm:4 \

qemu/target/arm/t32.decode

@@ -150,6 +150,15 @@ RSB_rri          1111 0.0 1110 . .... 0 ... .... ........     @s_rri_rot
   SUB_rri        1111 0.1 0101 0 .... 0 ... .... ........     @s0_rri_12
 }
 
+# Move Wide
+
+%imm16_26_16_12_0 16:4 26:1 12:3 0:8
+@mov16           .... .... .... .... .... rd:4 .... .... \
+                 &ri imm=%imm16_26_16_12_0
+
+MOVW             1111 0.10 0100 .... 0 ... .... ........      @mov16
+MOVT             1111 0.10 1100 .... 0 ... .... ........      @mov16
+
 # Saturate, bitfield
 
 @sat             .... .... .. sh:1 . rn:4 . ... rd:4 .. . satimm:5 \

qemu/target/arm/translate.c

@@ -8153,6 +8153,36 @@ static bool trans_ADR(DisasContext *s, arg_ri *a)
     return true;
 }
 
+static bool trans_MOVW(DisasContext *s, arg_MOVW *a)
+{
+    TCGContext *tcg_ctx = s->uc->tcg_ctx;
+    TCGv_i32 tmp;
+
+    if (!ENABLE_ARCH_6T2) {
+        return false;
+    }
+
+    tmp = tcg_const_i32(tcg_ctx, a->imm);
+    store_reg(s, a->rd, tmp);
+    return true;
+}
+
+static bool trans_MOVT(DisasContext *s, arg_MOVW *a)
+{
+    TCGContext *tcg_ctx = s->uc->tcg_ctx;
+    TCGv_i32 tmp;
+
+    if (!ENABLE_ARCH_6T2) {
+        return false;
+    }
+
+    tmp = load_reg(s, a->rd);
+    tcg_gen_ext16u_i32(tcg_ctx, tmp, tmp);
+    tcg_gen_ori_i32(tcg_ctx, tmp, tmp, a->imm << 16);
+    store_reg(s, a->rd, tmp);
+    return true;
+}
+
 /*
  * Multiply and multiply accumulate
  */
@@ -10090,7 +10120,7 @@ static bool trans_UDIV(DisasContext *s, arg_rrr *a)
 static void disas_arm_insn(DisasContext *s, unsigned int insn)
 {
     TCGContext *tcg_ctx = s->uc->tcg_ctx;
-    unsigned int cond, val, op1, i, rn, rd;
+    unsigned int cond, val, op1, i, rn;
     TCGv_i32 tmp;
     TCGv_i32 tmp2;
     TCGv_i32 addr;
@@ -10347,26 +10377,8 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn)
     /* fall back to legacy decoder */
 
     if ((insn & 0x0f900000) == 0x03000000) {
-        if ((insn & (1 << 21)) == 0) {
+        /* All done in decodetree.  Illegal ops reach here.  */
-            ARCH(6T2);
+        goto illegal_op;
-            rd = (insn >> 12) & 0xf;
-            val = ((insn >> 4) & 0xf000) | (insn & 0xfff);
-            if ((insn & (1 << 22)) == 0) {
-                /* MOVW */
-                tmp = tcg_temp_new_i32(tcg_ctx);
-                tcg_gen_movi_i32(tcg_ctx, tmp, val);
-            } else {
-                /* MOVT */
-                tmp = load_reg(s, rd);
-                tcg_gen_ext16u_i32(tcg_ctx, tmp, tmp);
-                tcg_gen_ori_i32(tcg_ctx, tmp, tmp, val << 16);
-            }
-            store_reg(s, rd, tmp);
-        } else {
-            /* MSR (immediate) and hints */
-            /* All done in decodetree.  Illegal ops already signalled.  */
-            g_assert_not_reached();
-        }
     } else if ((insn & 0x0f900000) == 0x01000000
                && (insn & 0x00000090) != 0x00000090) {
         /* miscellaneous instructions */
@@ -11102,42 +11114,9 @@ static void disas_thumb2_insn(DisasContext *s, uint32_t insn)
             /*
              * 0b1111_0xxx_xxxx_0xxx_xxxx_xxxx
              *  - Data-processing (modified immediate, plain binary immediate)
+             * All in decodetree.
              */
-            if (insn & (1 << 25)) {
+            goto illegal_op;
-                /*
-                 * 0b1111_0x1x_xxxx_0xxx_xxxx_xxxx
-                 *  - Data-processing (plain binary immediate)
-                 */
-                if (insn & (1 << 24)) {
-                    /* Bitfield/Saturate, in decodetree */
-                    goto illegal_op;
-                } else {
-                    imm = ((insn & 0x04000000) >> 15)
-                          | ((insn & 0x7000) >> 4) | (insn & 0xff);
-                    if (insn & (1 << 22)) {
-                        /* 16-bit immediate.  */
-                        imm |= (insn >> 4) & 0xf000;
-                        if (insn & (1 << 23)) {
-                            /* movt */
-                            tmp = load_reg(s, rd);
-                            tcg_gen_ext16u_i32(tcg_ctx, tmp, tmp);
-                            tcg_gen_ori_i32(tcg_ctx, tmp, tmp, imm << 16);
-                        } else {
-                            /* movw */
-                            tmp = tcg_temp_new_i32(tcg_ctx);
-                            tcg_gen_movi_i32(tcg_ctx, tmp, imm);
-                        }
-                        store_reg(s, rd, tmp);
-                    } else {
-                        /* Add/sub 12-bit immediate, in decodetree */
-                        goto illegal_op;
-                    }
-                }
-            } else {
-                /* Data-processing (modified immediate) */
-                /* All done in decodetree.  Reach here for illegal ops.  */
-                goto illegal_op;
-            }
         }
         break;
     case 12: