Implement more thumb branch instructions.

dpgeorge · dpgeorge · commit 1a6633a74d68 · 2013-11-03T13:58:19.000Z
diff --git a/py/asmthumb.c b/py/asmthumb.c
@@ -301,29 +301,16 @@ void asm_thumb_b_n(asm_thumb_t *as, int label) {
     }
 }
 
-#define OP_BEQ_N(byte_offset) (0xd000 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BNE_N(byte_offset) (0xd100 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BCS_N(byte_offset) (0xd200 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BCC_N(byte_offset) (0xd300 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BMI_N(byte_offset) (0xd400 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BPL_N(byte_offset) (0xd500 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BVS_N(byte_offset) (0xd600 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BVC_N(byte_offset) (0xd700 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BHI_N(byte_offset) (0xd800 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BLS_N(byte_offset) (0xd900 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BGE_N(byte_offset) (0xda00 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BLT_N(byte_offset) (0xdb00 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BGT_N(byte_offset) (0xdc00 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BLE_N(byte_offset) (0xdd00 | (((byte_offset) >> 1) & 0x00ff))
-
-void asm_thumb_bgt_n(asm_thumb_t *as, int label) {
+#define OP_BCC_N(cond, byte_offset) (0xd000 | ((cond) << 8) | (((byte_offset) >> 1) & 0x00ff))
+
+void asm_thumb_bcc_n(asm_thumb_t *as, int cond, int label) {
     int dest = get_label_dest(as, label);
     int 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_write_op16(as, OP_BGT_N(rel));
+        asm_thumb_write_op16(as, OP_BCC_N(cond, rel));
     } else {
-        printf("asm_thumb_bgt: branch does not fit in 9 bits\n");
+        printf("asm_thumb_bcc_n: branch does not fit in 9 bits\n");
     }
 }
 
@@ -408,32 +395,25 @@ void asm_thumb_b_label(asm_thumb_t *as, int label) {
 }
 
 // all these bit arithmetics need coverage testing!
-#define OP_BEQ(byte_offset) (0xd000 | (((byte_offset) >> 1) & 0x00ff))
-#define OP_BEQW_HI(byte_offset) (0xf000 | (((byte_offset) >> 10) & 0x0400) | (((byte_offset) >> 14) & 0x003f))
-#define OP_BEQW_LO(byte_offset) (0x8000 | ((byte_offset) & 0x2000) | (((byte_offset) >> 1) & 0x0fff))
-
-void asm_thumb_cmp_reg_bz_label(asm_thumb_t *as, uint rlo, int label) {
-    assert(rlo < REG_R8);
-
-    // compare reg with 0
-    asm_thumb_write_op16(as, OP_CMP_RLO_I8(rlo, 0));
+#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))
 
-    // branch if equal
+void asm_thumb_bcc_label(asm_thumb_t *as, int cond, int label) {
     int dest = get_label_dest(as, label);
     int rel = dest - as->code_offset;
     rel -= 4; // account for instruction prefetch, PC is 4 bytes ahead of this instruction
     if (dest >= 0 && rel <= -4) {
         // is a backwards jump, so we know the size of the jump on the first pass
         // calculate rel assuming 9 bit relative jump
         if (SIGNED_FIT9(rel)) {
-            asm_thumb_write_op16(as, OP_BEQ(rel));
+            asm_thumb_write_op16(as, OP_BCC_N(cond, rel));
         } else {
             goto large_jump;
         }
     } else {
         // is a forwards jump, so need to assume it's large
         large_jump:
-        asm_thumb_write_op32(as, OP_BEQW_HI(rel), OP_BEQW_LO(rel));
+        asm_thumb_write_op32(as, OP_BCC_W_HI(cond, rel), OP_BCC_W_LO(rel));
     }
 }
 
diff --git a/py/asmthumb.h b/py/asmthumb.h
@@ -26,6 +26,21 @@
 #define REG_ARG_3 REG_R2
 #define REG_ARG_4 REG_R3
 
+#define THUMB_CC_EQ (0x0)
+#define THUMB_CC_NE (0x1)
+#define THUMB_CC_CS (0x2)
+#define THUMB_CC_CC (0x3)
+#define THUMB_CC_MI (0x4)
+#define THUMB_CC_PL (0x5)
+#define THUMB_CC_VS (0x6)
+#define THUMB_CC_VC (0x7)
+#define THUMB_CC_HI (0x8)
+#define THUMB_CC_LS (0x9)
+#define THUMB_CC_GE (0xa)
+#define THUMB_CC_LT (0xb)
+#define THUMB_CC_GT (0xc)
+#define THUMB_CC_LE (0xd)
+
 typedef struct _asm_thumb_t asm_thumb_t;
 
 asm_thumb_t *asm_thumb_new(uint max_num_labels);
@@ -50,7 +65,7 @@ void asm_thumb_mov_reg_reg(asm_thumb_t *as, uint reg_dest, uint reg_src);
 void asm_thumb_subs_rlo_rlo_i3(asm_thumb_t *as, uint rlo_dest, uint rlo_src, int i3_src);
 void asm_thumb_cmp_rlo_i8(asm_thumb_t *as, uint rlo, int i8);
 void asm_thumb_b_n(asm_thumb_t *as, int label);
-void asm_thumb_bgt_n(asm_thumb_t *as, int label);
+void asm_thumb_bcc_n(asm_thumb_t *as, int cond, int label);
 
 void asm_thumb_mov_reg_i32(asm_thumb_t *as, uint reg_dest, machine_uint_t i32_src); // convenience
 void asm_thumb_mov_reg_i32_optimised(asm_thumb_t *as, uint reg_dest, int i32_src); // convenience
@@ -63,6 +78,6 @@ void asm_thumb_cmp_reg_reg(asm_thumb_t *as, uint rlo_a, uint rlo_b); // convenie
 void asm_thumb_ite_ge(asm_thumb_t *as); // convenience ?
 
 void asm_thumb_b_label(asm_thumb_t *as, int label); // convenience ?
-void asm_thumb_cmp_reg_bz_label(asm_thumb_t *as, uint rlo, int label); // convenience ?
+void asm_thumb_bcc_label(asm_thumb_t *as, int cc, int label); // convenience: picks narrow or wide branch
 void asm_thumb_bl_ind(asm_thumb_t *as, void *fun_ptr, uint fun_id, uint reg_temp); // convenience ?
 
diff --git a/py/emitinlinethumb.c b/py/emitinlinethumb.c
@@ -154,7 +154,7 @@ static void emit_inline_thumb_op(emit_inline_asm_t *emit, qstr op, int n_args, p
         }
         int label_num = get_arg_label(emit, op, pn_args, 0);
         // TODO check that this succeeded, ie branch was within range
-        asm_thumb_bgt_n(emit->as, label_num);
+        asm_thumb_bcc_n(emit->as, THUMB_CC_GT, label_num);
 
     // 2 args
     } else if (strcmp(qstr_str(op), "movs") == 0) {
diff --git a/py/emitnative.c b/py/emitnative.c
@@ -871,7 +871,7 @@ static void emit_native_jump(emit_t *emit, int label) {
     emit_post(emit);
 }
 
-static void emit_native_pop_jump_if_false(emit_t *emit, int label) {
+static void emit_native_pop_jump_pre_helper(emit_t *emit, int label) {
     vtype_kind_t vtype = peek_vtype(emit);
     if (vtype == VTYPE_BOOL) {
         emit_pre_pop_reg(emit, &vtype, REG_RET);
@@ -882,18 +882,32 @@ static void emit_native_pop_jump_if_false(emit_t *emit, int label) {
         printf("ViperTypeError: expecting a bool or pyobj, got %d\n", vtype);
         assert(0);
     }
+}
+
+static void emit_native_pop_jump_if_false(emit_t *emit, int label) {
+    emit_native_pop_jump_pre_helper(emit, label);
 #if N_X64
     asm_x64_test_r8_with_r8(emit->as, REG_RET, REG_RET);
     asm_x64_jcc_label(emit->as, JCC_JZ, label);
 #elif N_THUMB
-    asm_thumb_cmp_reg_bz_label(emit->as, REG_RET, label);
+    asm_thumb_cmp_rlo_i8(emit->as, REG_RET, 0);
+    asm_thumb_bcc_label(emit->as, THUMB_CC_EQ, label);
 #endif
     emit_post(emit);
 }
 
 static void emit_native_pop_jump_if_true(emit_t *emit, int label) {
-    assert(0);
+    emit_native_pop_jump_pre_helper(emit, label);
+#if N_X64
+    asm_x64_test_r8_with_r8(emit->as, REG_RET, REG_RET);
+    asm_x64_jcc_label(emit->as, JCC_JNZ, label);
+#elif N_THUMB
+    asm_thumb_cmp_rlo_i8(emit->as, REG_RET, 0);
+    asm_thumb_bcc_label(emit->as, THUMB_CC_NE, label);
+#endif
+    emit_post(emit);
 }
+
 static void emit_native_jump_if_true_or_pop(emit_t *emit, int label) {
     assert(0);
 }

Original file line number	Diff line number	Diff line change
`@@ -154,7 +154,7 @@ static void emit_inline_thumb_op(emit_inline_asm_t *emit, qstr op, int n_args, p`
`154`	`154`	`}`
`155`	`155`	`int label_num = get_arg_label(emit, op, pn_args, 0);`
`156`	`156`	`// TODO check that this succeeded, ie branch was within range`
`157`		`- asm_thumb_bgt_n(emit->as, label_num);`
	`157`	`+ asm_thumb_bcc_n(emit->as, THUMB_CC_GT, label_num);`
`158`	`158`
`159`	`159`	`// 2 args`
`160`	`160`	`} else if (strcmp(qstr_str(op), "movs") == 0) {`