static LLVMValueRef assign_rvalue(compile_t* c, ast_t* left, ast_t* r_type,
LLVMValueRef r_value)
{
switch(ast_id(left))
{
case TK_VAR:
case TK_LET:
{
// Generate the locals.
if(gen_localdecl(c, left) == NULL)
return NULL;
return assign_rvalue(c, ast_child(left), r_type, r_value);
}
case TK_FVARREF:
case TK_FLETREF:
{
// The result is the previous value of the field.
LLVMValueRef l_value = gen_fieldptr(c, left);
return assign_one(c, l_value, r_value, r_type);
}
case TK_VARREF:
{
// The result is the previous value of the local.
LLVMValueRef l_value = gen_localptr(c, left);
return assign_one(c, l_value, r_value, r_type);
}
case TK_TUPLE:
{
// If the l_value is a tuple, assemble it as the result.
LLVMValueRef result = gen_expr(c, left);
if(result == NULL)
return NULL;
if(!assign_tuple(c, left, r_type, r_value))
return NULL;
// Return the original tuple.
return result;
}
case TK_ID:
{
// We may have recursed here from a VAR or LET or arrived directly.
const char* name = ast_name(left);
LLVMValueRef l_value = codegen_getlocal(c, name);
return assign_one(c, l_value, r_value, r_type);
}
default: {}
}
assert(0);
return NULL;
}
LLVMValueRef gen_assign_value(compile_t* c, ast_t* left, LLVMValueRef right,
ast_t* right_type)
{
// Must generate the right hand side before the left hand side.
if(right == NULL)
return NULL;
// This is from pattern matching and we should not generate the alloca again.
return assign_rvalue(c, ast_child(left), right_type, right);
}
static bool assign_tuple(compile_t* c, ast_t* left, ast_t* r_type,
LLVMValueRef r_value)
{
// Handle assignment for each component.
ast_t* child = ast_child(left);
ast_t* rtype_child = ast_child(r_type);
int i = 0;
while(child != NULL)
{
ast_t* expr = NULL;
switch(ast_id(child))
{
case TK_SEQ:
// The actual tuple expression is inside a sequence node.
expr = ast_child(child);
break;
case TK_LET:
case TK_VAR:
case TK_TUPLE:
expr = child;
break;
case TK_DONTCARE:
// Ignore this element.
break;
default:
assert(0);
}
if(expr != NULL)
{
// Extract the tuple value.
LLVMValueRef rvalue_child = LLVMBuildExtractValue(c->builder, r_value, i,
"");
// Recurse, assigning pairwise.
if(assign_rvalue(c, expr, rtype_child, rvalue_child) == NULL)
return false;
}
i++;
child = ast_sibling(child);
rtype_child = ast_sibling(rtype_child);
}
assert(rtype_child == NULL);
return true;
}
LLVMValueRef gen_assign(compile_t* c, ast_t* ast)
{
// Must generate the right hand side before the left hand side. Left and
// right are swapped for type checking, so we fetch them in reverse order.
AST_GET_CHILDREN(ast, right, left);
LLVMValueRef r_value = gen_expr(c, right);
// Emit debug location of assignment expression
dwarf_location(&c->dwarf, ast);
if(r_value == NULL)
return NULL;
return assign_rvalue(c, left, ast_type(right), r_value);
}
LLVMValueRef gen_assign(compile_t* c, ast_t* ast)
{
// Must generate the right hand side before the left hand side. Left and
// right are swapped for type checking, so we fetch them in reverse order.
AST_GET_CHILDREN(ast, right, left);
LLVMValueRef r_value = gen_expr(c, right);
if(r_value == NULL)
return NULL;
codegen_debugloc(c, ast);
LLVMValueRef result = assign_rvalue(c, left, ast_type(right), r_value);
codegen_debugloc(c, NULL);
return result;
}
static LLVMValueRef assign_rvalue(compile_t* c, ast_t* left, ast_t* r_type,
LLVMValueRef r_value)
{
switch(ast_id(left))
{
case TK_SEQ:
// The actual expression is inside a sequence node.
while(ast_id(left) == TK_SEQ)
{
assert(ast_childcount(left) == 1);
left = ast_child(left);
}
return assign_rvalue(c, left, r_type, r_value);
case TK_VAR:
case TK_LET:
{
// Generate the locals.
if(gen_localdecl(c, left) == NULL)
return NULL;
return assign_rvalue(c, ast_child(left), r_type, r_value);
}
case TK_FVARREF:
case TK_FLETREF:
{
// The result is the previous value of the field.
LLVMValueRef l_value = gen_fieldptr(c, left);
return assign_one(c, l_value, r_value, r_type);
}
case TK_EMBEDREF:
{
// Do nothing. The embed field was already passed as the receiver.
return GEN_NOVALUE;
}
case TK_VARREF:
{
// The result is the previous value of the local.
LLVMValueRef l_value = gen_localptr(c, left);
return assign_one(c, l_value, r_value, r_type);
}
case TK_TUPLE:
{
// If the l_value is a tuple, assemble it as the result.
LLVMValueRef result = gen_expr(c, left);
if(result == NULL)
return NULL;
if(!assign_tuple(c, left, r_type, r_value))
return NULL;
// Return the original tuple.
return result;
}
case TK_ID:
{
// We may have recursed here from a VAR or LET or arrived directly.
const char* name = ast_name(left);
LLVMValueRef l_value = codegen_getlocal(c, name);
return assign_one(c, l_value, r_value, r_type);
}
default: {}
}
assert(0);
return NULL;
}
