py: For inline assembler, add bcc_n and bcc_w ops.

Addresses issue #1143.

py/asmthumb.c

@@ -307,15 +307,24 @@ bool asm_thumb_b_n_label(asm_thumb_t *as, uint label) {
 
 #define OP_BCC_N(cond, byte_offset) (0xd000 | ((cond) << 8) | (((byte_offset) >> 1) & 0x00ff))
 
-bool asm_thumb_bcc_n_label(asm_thumb_t *as, int cond, uint label) {
+// all these bit arithmetics need coverage testing!
+#define OP_BCC_W_HI(cond, byte_offset) (0xf000 | ((cond) << 6) | (((byte_offset) >> 10) & 0x0400) | (((byte_offset) >> 14) & 0x003f))
+#define OP_BCC_W_LO(byte_offset) (0x8000 | ((byte_offset) & 0x2000) | (((byte_offset) >> 1) & 0x0fff))
+
+bool asm_thumb_bcc_nw_label(asm_thumb_t *as, int cond, uint label, bool wide) {
     mp_uint_t dest = get_label_dest(as, label);
     mp_int_t rel = dest - as->code_offset;
     rel -= 4; // account for instruction prefetch, PC is 4 bytes ahead of this instruction
-    if (SIGNED_FIT9(rel)) {
-        asm_thumb_op16(as, OP_BCC_N(cond, rel));
-        return true;
+    if (!wide) {
+        if (SIGNED_FIT9(rel)) {
+            asm_thumb_op16(as, OP_BCC_N(cond, rel));
+            return true;
+        } else {
+            return false;
+        }
     } else {
-        return false;
+        asm_thumb_op32(as, OP_BCC_W_HI(cond, rel), OP_BCC_W_LO(rel));
+        return true;
     }
 }
 
@@ -416,10 +425,6 @@ void asm_thumb_b_label(asm_thumb_t *as, uint label) {
     }
 }
 
-// all these bit arithmetics need coverage testing!
-#define OP_BCC_W_HI(cond, byte_offset) (0xf000 | ((cond) << 6) | (((byte_offset) >> 10) & 0x0400) | (((byte_offset) >> 14) & 0x003f))
-#define OP_BCC_W_LO(byte_offset) (0x8000 | ((byte_offset) & 0x2000) | (((byte_offset) >> 1) & 0x0fff))
-
 void asm_thumb_bcc_label(asm_thumb_t *as, int cond, uint label) {
     mp_uint_t dest = get_label_dest(as, label);
     mp_int_t rel = dest - as->code_offset;

py/asmthumb.h

@@ -216,7 +216,7 @@ void asm_thumb_mov_reg_i16(asm_thumb_t *as, uint mov_op, uint reg_dest, int i16_
 
 // these return true if the destination is in range, false otherwise
 bool asm_thumb_b_n_label(asm_thumb_t *as, uint label);
-bool asm_thumb_bcc_n_label(asm_thumb_t *as, int cond, uint label);
+bool asm_thumb_bcc_nw_label(asm_thumb_t *as, int cond, uint label, bool wide);
 bool asm_thumb_bl_label(asm_thumb_t *as, uint label);
 
 void asm_thumb_mov_reg_i32(asm_thumb_t *as, uint reg_dest, mp_uint_t i32_src); // convenience

py/emitinlinethumb.c

@@ -378,7 +378,9 @@ STATIC void emit_inline_thumb_op(emit_inline_asm_t *emit, qstr op, mp_uint_t n_a
         } else if (strcmp(op_str, "bx") == 0) {
             mp_uint_t r = get_arg_reg(emit, op_str, pn_args[0], 15);
             asm_thumb_op16(emit->as, 0x4700 | (r << 3));
-        } else if (op_str[0] == 'b' && op_len == 3) {
+        } else if (op_str[0] == 'b' && (op_len == 3
+                    || (op_len == 5 && op_str[3] == '_'
+                        && (op_str[4] == 'n' || op_str[4] == 'w')))) {
             mp_uint_t cc = -1;
             for (mp_uint_t i = 0; i < MP_ARRAY_SIZE(cc_name_table); i++) {
                 if (op_str[1] == cc_name_table[i].name[0] && op_str[2] == cc_name_table[i].name[1]) {
@@ -389,7 +391,7 @@ STATIC void emit_inline_thumb_op(emit_inline_asm_t *emit, qstr op, mp_uint_t n_a
                 goto unknown_op;
             }
             int label_num = get_arg_label(emit, op_str, pn_args[0]);
-            if (!asm_thumb_bcc_n_label(emit->as, cc, label_num)) {
+            if (!asm_thumb_bcc_nw_label(emit->as, cc, label_num, op_len == 5 && op_str[4] == 'w')) {
                 goto branch_not_in_range;
             }
         } else if (op_str[0] == 'i' && op_str[1] == 't') {