+ add "fingerprints" in the beginning of each routine for easier debugging (this

  will be disabled later, and only enabled with -g or some other target flag,
  but for now, it's always on)

git-svn-id: branches/wasm@48272 -

compiler/wasm32/hlcgcpu.pas

@@ -201,6 +201,19 @@ uses
         slots used for parameters and the provided resultdef }
       procedure g_adjust_stack_after_call(list: TAsmList; pd: tabstractprocdef);
 
+      { because WebAssembly has no spec for any sort of debug info, and the
+        only linker that we support (LLVM's wasm-ld) does not support creating
+        map files in its stable version, and crashes when attempting to create
+        a map file in its development version from git, we have no way to
+        identify which procedure a crash occurred in. So, to identify the
+        procedure, we call this procedure on proc entry, which generates a few
+        useless loads of random numbers on the stack, that are immediately
+        discarded, so they are essentially equivalent to a nop. This allows
+        finding the procedure in the FPC output assembly, produced with -al by
+        searching for these random numbers, as taken from the disassembly of the
+        final binary. }
+      procedure g_fingerprint(list: TAsmList);
+
       property maxevalstackheight: longint read fmaxevalstackheight;
 
      protected
@@ -1510,6 +1523,8 @@ implementation
       list.Concat(tai_local.create(wbt_i32,FRAME_POINTER_SYM)); //TWasmBasicType
       list.Concat(tai_local.create(wbt_i32,BASE_POINTER_SYM)); //TWasmBasicType
 
+      g_fingerprint(list);
+
       list.Concat(taicpu.op_sym(a_get_global,current_asmdata.RefAsmSymbol(STACK_POINTER_SYM,AT_LABEL)));
       incstack(list,1);
       list.Concat(taicpu.op_ref(a_set_local,pd.base_pointer_ref));
@@ -1951,6 +1966,19 @@ implementation
     end;
 
 
+  procedure thlcgwasm.g_fingerprint(list: TAsmList);
+    begin
+      list.concat(taicpu.op_const(a_i64_const,Random(high(int64))));
+      list.concat(taicpu.op_const(a_i64_const,Random(high(int64))));
+      list.concat(taicpu.op_const(a_i64_const,Random(high(int64))));
+      list.concat(taicpu.op_const(a_i64_const,Random(high(int64))));
+      list.concat(taicpu.op_none(a_drop));
+      list.concat(taicpu.op_none(a_drop));
+      list.concat(taicpu.op_none(a_drop));
+      list.concat(taicpu.op_none(a_drop));
+    end;
+
+
   procedure thlcgwasm.resizestackfpuval(list: TAsmList; fromsize, tosize: tcgsize);
     begin
       if (fromsize=OS_F32) and