tcg/arm: add variables to define the allowed instructions set

Use a set of variables to define the allowed ARM instructions, depending
on the __ARM_ARCH_*__ GCC defines.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

tcg/arm/tcg-target.c

@@ -22,6 +22,51 @@
  * THE SOFTWARE.
  */
 
+#if defined(__ARM_ARCH_7__) ||  \
+    defined(__ARM_ARCH_7A__) || \
+    defined(__ARM_ARCH_7EM__) || \
+    defined(__ARM_ARCH_7M__) || \
+    defined(__ARM_ARCH_7R__)
+#define USE_ARMV7_INSTRUCTIONS
+#endif
+
+#if defined(USE_ARMV7_INSTRUCTIONS) || \
+    defined(__ARM_ARCH_6J__) || \
+    defined(__ARM_ARCH_6K__) || \
+    defined(__ARM_ARCH_6T2__) || \
+    defined(__ARM_ARCH_6Z__) || \
+    defined(__ARM_ARCH_6ZK__)
+#define USE_ARMV6_INSTRUCTIONS
+#endif
+
+#if defined(USE_ARMV6_INSTRUCTIONS) || \
+    defined(__ARM_ARCH_5T__) || \
+    defined(__ARM_ARCH_5TE__) || \
+    defined(__ARM_ARCH_5TEJ__)
+#define USE_ARMV5_INSTRUCTIONS
+#endif
+
+#ifdef USE_ARMV5_INSTRUCTIONS
+static const int use_armv5_instructions = 1;
+#else
+static const int use_armv5_instructions = 0;
+#endif
+#undef USE_ARMV5_INSTRUCTIONS
+
+#ifdef USE_ARMV6_INSTRUCTIONS
+static const int use_armv6_instructions = 1;
+#else
+static const int use_armv6_instructions = 0;
+#endif
+#undef USE_ARMV6_INSTRUCTIONS
+
+#ifdef USE_ARMV7_INSTRUCTIONS
+static const int use_armv7_instructions = 1;
+#else
+static const int use_armv7_instructions = 0;
+#endif
+#undef USE_ARMV7_INSTRUCTIONS
+
 #ifndef NDEBUG
 static const char * const tcg_target_reg_names[TCG_TARGET_NB_REGS] = {
     "%r0",
@@ -361,7 +406,7 @@ static inline void tcg_out_movi32(TCGContext *s,
                 tcg_out_dat_imm(s, cond, ARITH_ADD, rd, 15, offset) :
                 tcg_out_dat_imm(s, cond, ARITH_SUB, rd, 15, -offset);
 
-#ifdef __ARM_ARCH_7A__
+    if (use_armv7_instructions) {
         /* use movw/movt */
         /* movw */
         tcg_out32(s, (cond << 28) | 0x03000000 | (rd << 12)
@@ -370,7 +415,7 @@ static inline void tcg_out_movi32(TCGContext *s,
             /* movt */
             tcg_out32(s, (cond << 28) | 0x03400000 | (rd << 12)
                       | ((arg >> 12) & 0x000f0000) | ((arg >> 16) & 0xfff));
-#else
+    } else {
         tcg_out_dat_imm(s, cond, ARITH_MOV, rd, 0, arg & 0xff);
         if (arg & 0x0000ff00)
             tcg_out_dat_imm(s, cond, ARITH_ORR, rd, rd,
@@ -381,7 +426,7 @@ static inline void tcg_out_movi32(TCGContext *s,
         if (arg & 0xff000000)
             tcg_out_dat_imm(s, cond, ARITH_ORR, rd, rd,
                             ((arg >> 24) & 0xff) | 0x400);
-#endif
+        }
 }
 
 static inline void tcg_out_mul32(TCGContext *s,
@@ -1433,26 +1478,26 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc,
         break;
 
     case INDEX_op_ext8s_i32:
-#ifdef __ARM_ARCH_7A__
+        if (use_armv7_instructions) {
             /* sxtb */
             tcg_out32(s, 0xe6af0070 | (args[0] << 12) | args[1]);
-#else
+        } else {
             tcg_out_dat_reg(s, COND_AL, ARITH_MOV,
                             args[0], 0, args[1], SHIFT_IMM_LSL(24));
             tcg_out_dat_reg(s, COND_AL, ARITH_MOV,
                             args[0], 0, args[0], SHIFT_IMM_ASR(24));
-#endif
+        }
         break;
     case INDEX_op_ext16s_i32:
-#ifdef __ARM_ARCH_7A__
+        if (use_armv7_instructions) {
             /* sxth */
             tcg_out32(s, 0xe6bf0070 | (args[0] << 12) | args[1]);
-#else
+        } else {
             tcg_out_dat_reg(s, COND_AL, ARITH_MOV,
                             args[0], 0, args[1], SHIFT_IMM_LSL(16));
             tcg_out_dat_reg(s, COND_AL, ARITH_MOV,
                             args[0], 0, args[0], SHIFT_IMM_ASR(16));
-#endif
+        }
         break;
 
     default: