more type validation during compilation

source/m3_compile.c

@@ -498,17 +498,17 @@ M3Result  Pop  (IM3Compilation o)
 
 M3Result  PopType  (IM3Compilation o, u8 i_type)
 {
-	M3Result result = m3Err_none;
-	
-	u8 topType = GetStackTopType (o);
-	
-	if (i_type == topType)
-	{
-		result = Pop (o);
-	}
-	else result = m3Err_typeMismatch;
-	
-	return result;
+    M3Result result = m3Err_none;
+    
+    u8 topType = GetStackTopType (o);
+    
+    if (i_type == topType or o->block.isPolymorphic)
+    {
+        result = Pop (o);
+    }
+    else result = m3Err_typeMismatch;
+    
+    return result;
 }
 
 
@@ -1010,8 +1010,8 @@ M3Result  Compile_Return  (IM3Compilation o, m3opcode_t i_opcode)
 
     if (GetFunctionNumReturns (o->function))
     {
-		u8 type = GetFunctionReturnType (o->function, 0);
-		
+        u8 type = GetFunctionReturnType (o->function, 0);
+        
 _       (ReturnStackTop (o));
 _       (PopType (o, type));
     }
@@ -1035,9 +1035,9 @@ M3Result  Compile_End  (IM3Compilation o, m3opcode_t i_opcode)
 
         if (type)
         {
-			if (type != GetStackTopType (o))
-				_throw (m3Err_typeMismatch);
-			
+            if (not o->block.isPolymorphic and type != GetStackTopType (o))
+                _throw (m3Err_typeMismatch);
+            
             // if there are branches to the function end, then their values are in a register
             // if the block happens to have its top in a register too, then we can patch the branch
             // to here. Otherwise, an ReturnStackTop is appended to the end of the function (at B) and

source/m3_env.c

@@ -162,14 +162,14 @@ u32  GetFunctionNumReturns  (IM3Function i_function)
 
 u8  GetFunctionReturnType  (IM3Function i_function, u32 i_index)
 {
-	u8 type = c_m3Type_none;
-	
-	if (i_index < GetFunctionNumReturns (i_function))
-	{
-		type = i_function->funcType->types [i_index];
-	}
-	
-	return type;
+    u8 type = c_m3Type_none;
+    
+    if (i_index < GetFunctionNumReturns (i_function))
+    {
+        type = i_function->funcType->types [i_index];
+    }
+    
+    return type;
 }
 
 

source/m3_env.h

@@ -68,7 +68,7 @@ cstr_t      GetFunctionImportModuleName (IM3Function i_function);
 cstr_t *    GetFunctionNames            (IM3Function i_function, u16 * o_numNames);
 u32         GetFunctionNumArgs          (IM3Function i_function);
 u32         GetFunctionNumReturns       (IM3Function i_function);
-u8 			GetFunctionReturnType		(IM3Function i_function, u32 i_index);
+u8          GetFunctionReturnType       (IM3Function i_function, u32 i_index);
 
 u32         GetFunctionNumArgsAndLocals (IM3Function i_function);
 

source/wasm3.h

@@ -135,7 +135,7 @@ d_m3ErrorConst  (functionStackOverflow,         "compiling function overran its
 d_m3ErrorConst  (functionStackUnderrun,         "compiling function underran the stack")
 d_m3ErrorConst  (mallocFailedCodePage,          "memory allocation failed when acquiring a new M3 code page")
 d_m3ErrorConst  (settingImmutableGlobal,        "attempting to set an immutable global")
-d_m3ErrorConst  (typeMismatch,  		      	"malformed Wasm: incorrect type on stack")
+d_m3ErrorConst  (typeMismatch,                  "malformed Wasm: incorrect type on stack")
 
 // runtime errors
 d_m3ErrorConst  (missingCompiledCode,           "function is missing compiled m3 code")