Implement source debugging for interpreter and AOT (#769)

Implement source debugging feature for classic interpreter and AOT:
- use `cmake -DWAMR_BUILD_DEBUG_INTERP=1` to enable interpreter debugging
- use `cmake -DWAMR_BUILD_DEBUG_AOT=1` to enable AOT debugging

See doc/source_debugging.md for more details.

core/iwasm/compilation/aot_emit_control.c

@@ -8,6 +8,10 @@
 #include "../aot/aot_runtime.h"
 #include "../interpreter/wasm_loader.h"
 
+#if WASM_ENABLE_DEBUG_AOT != 0
+#include "debug/dwarf_extractor.h"
+#endif
+
 static char *block_name_prefix[] = { "block", "loop", "if" };
 static char *block_name_suffix[] = { "begin", "else", "end" };
 
@@ -158,14 +162,22 @@ handle_next_reachable_block(AOTCompContext *comp_ctx,
     uint8 *frame_ip = NULL;
     uint32 i;
     AOTFuncType *func_type;
+    LLVMValueRef ret;
+#if WASM_ENABLE_DEBUG_AOT != 0
+    LLVMMetadataRef return_location;
+#endif
 
     aot_checked_addr_list_destroy(func_ctx);
-
     bh_assert(block);
 
+#if WASM_ENABLE_DEBUG_AOT != 0
+    return_location = dwarf_gen_location(
+      comp_ctx, func_ctx,
+      (*p_frame_ip - 1) - comp_ctx->comp_data->wasm_module->buf_code
+    );
+#endif
     if (block->label_type == LABEL_TYPE_IF
         && block->llvm_else_block
-        && !block->skip_wasm_code_else
         && *p_frame_ip <= block->wasm_code_else) {
         /* Clear value stack and start to translate else branch */
         aot_value_stack_destroy(&block->value_stack);
@@ -237,16 +249,23 @@ handle_next_reachable_block(AOTCompContext *comp_ctx,
     if (block->label_type == LABEL_TYPE_FUNCTION) {
         if (block->result_count) {
             /* Return the first return value */
-            if (!LLVMBuildRet(comp_ctx->builder, block->result_phis[0])) {
+            if (!(ret =
+                    LLVMBuildRet(comp_ctx->builder, block->result_phis[0]))) {
                 aot_set_last_error("llvm build return failed.");
                 goto fail;
             }
+#if WASM_ENABLE_DEBUG_AOT != 0
+            LLVMInstructionSetDebugLoc(ret, return_location);
+#endif
         }
         else {
-            if (!LLVMBuildRetVoid(comp_ctx->builder)) {
+            if (!(ret = LLVMBuildRetVoid(comp_ctx->builder))) {
                 aot_set_last_error("llvm build return void failed.");
                 goto fail;
             }
+#if WASM_ENABLE_DEBUG_AOT != 0
+            LLVMInstructionSetDebugLoc(ret, return_location);
+#endif
         }
     }
     aot_block_destroy(block);
@@ -381,7 +400,7 @@ aot_compile_op_block(AOTCompContext *comp_ctx, AOTFuncContext *func_ctx,
     memset(block_addr_cache, 0, sizeof(block_addr_cache));
 
     /* Get block info */
-    if (!(wasm_loader_find_block_addr((BlockAddr*)block_addr_cache,
+    if (!(wasm_loader_find_block_addr(NULL, (BlockAddr*)block_addr_cache,
                                       *p_frame_ip, frame_ip_end, (uint8)label_type,
                                       &else_addr, &end_addr))) {
         aot_set_last_error("find block end addr failed.");
@@ -709,7 +728,7 @@ check_suspend_flags(AOTCompContext *comp_ctx, AOTFuncContext *func_ctx)
 
     /* Move builder to terminate block */
     SET_BUILDER_POS(terminate_block);
-    if (!aot_build_zero_function_ret(comp_ctx, aot_func_type)) {
+    if (!aot_build_zero_function_ret(comp_ctx, func_ctx, aot_func_type)) {
         goto fail;
     }
 
@@ -1070,12 +1089,22 @@ aot_compile_op_return(AOTCompContext *comp_ctx, AOTFuncContext *func_ctx,
 {
     AOTBlock *block_func = func_ctx->block_stack.block_list_head;
     LLVMValueRef value;
+    LLVMValueRef ret;
     AOTFuncType *func_type;
     uint32 i, param_index, result_index;
+#if WASM_ENABLE_DEBUG_AOT != 0
+    LLVMMetadataRef return_location;
+#endif
 
     bh_assert(block_func);
     func_type = func_ctx->aot_func->func_type;
 
+#if WASM_ENABLE_DEBUG_AOT != 0
+    return_location = dwarf_gen_location(
+      comp_ctx, func_ctx,
+      (*p_frame_ip - 1) - comp_ctx->comp_data->wasm_module->buf_code
+    );
+#endif
     if (block_func->result_count) {
         /* Store extra result values to function parameters */
         for (i = 0; i < block_func->result_count - 1; i++) {
@@ -1091,16 +1120,22 @@ aot_compile_op_return(AOTCompContext *comp_ctx, AOTFuncContext *func_ctx,
         }
         /* Return the first result value */
         POP(value, block_func->result_types[0]);
-        if (!LLVMBuildRet(comp_ctx->builder, value)) {
+        if (!(ret = LLVMBuildRet(comp_ctx->builder, value))) {
             aot_set_last_error("llvm build return failed.");
             goto fail;
         }
+#if WASM_ENABLE_DEBUG_AOT != 0
+        LLVMInstructionSetDebugLoc(ret, return_location);
+#endif
     }
     else {
-        if (!LLVMBuildRetVoid(comp_ctx->builder)) {
+        if (!(ret = LLVMBuildRetVoid(comp_ctx->builder))) {
             aot_set_last_error("llvm build return void failed.");
             goto fail;
         }
+#if WASM_ENABLE_DEBUG_AOT != 0
+        LLVMInstructionSetDebugLoc(ret, return_location);
+#endif
     }
 
     return handle_next_reachable_block(comp_ctx, func_ctx, p_frame_ip);