This patch from Chris Manghane changes the Go frontend to use the
backend interface for unary expressions. Bootstrapped and ran Go
testsuite on x86_64-unknown-linux-gnu. Committed to mainline.
Ian
2014-01-24 Chris Manghane <cm...@google.com>
* go-gcc.cc (Gcc_backend::unary_expression): New function.
Index: gcc/go/gofrontend/expressions.cc
===================================================================
--- gcc/go/gofrontend/expressions.cc (revision 206904)
+++ gcc/go/gofrontend/expressions.cc (working copy)
@@ -1464,6 +1464,10 @@ class Func_code_reference_expression : p
do_traverse(Traverse*)
{ return TRAVERSE_CONTINUE; }
+ bool
+ do_is_immutable() const
+ { return true; }
+
Type*
do_type()
{ return Type::make_pointer_type(Type::make_void_type()); }
@@ -2941,6 +2945,10 @@ class Nil_expression : public Expression
do_is_constant() const
{ return true; }
+ bool
+ do_is_immutable() const
+ { return true; }
+
Type*
do_type()
{ return Type::make_nil_type(); }
@@ -3682,10 +3690,17 @@ class Unary_expression : public Expressi
Expression*
do_lower(Gogo*, Named_object*, Statement_inserter*, int);
+ Expression*
+ do_flatten(Gogo*, Named_object*, Statement_inserter*);
+
bool
do_is_constant() const;
bool
+ do_is_immutable() const
+ { return this->expr_->is_immutable(); }
+
+ bool
do_numeric_constant_value(Numeric_constant*) const;
Type*
@@ -3806,6 +3821,45 @@ Unary_expression::do_lower(Gogo*, Named_
return this;
}
+// Flatten expression if a nil check must be performed and create temporary
+// variables if necessary.
+
+Expression*
+Unary_expression::do_flatten(Gogo* gogo, Named_object*,
+ Statement_inserter* inserter)
+{
+ Location location = this->location();
+ if (this->op_ == OPERATOR_MULT
+ && !this->expr_->is_variable())
+ {
+ go_assert(this->expr_->type()->points_to() != NULL);
+ Type* ptype = this->expr_->type()->points_to();
+ if (!ptype->is_void_type())
+ {
+ Btype* pbtype = ptype->get_backend(gogo);
+ size_t s = gogo->backend()->type_size(pbtype);
+ if (s >= 4096 || this->issue_nil_check_)
+ {
+ Temporary_statement* temp =
+ Statement::make_temporary(NULL, this->expr_, location);
+ inserter->insert(temp);
+ this->expr_ =
+ Expression::make_temporary_reference(temp, location);
+ }
+ }
+ }
+
+ if (this->create_temp_ && !this->expr_->is_variable())
+ {
+ Temporary_statement* temp =
+ Statement::make_temporary(NULL, this->expr_, location);
+ inserter->insert(temp);
+ this->expr_ = Expression::make_temporary_reference(temp, location);
+ }
+
+ return this;
+}
+
// Return whether a unary expression is a constant.
bool
@@ -3821,8 +3875,8 @@ Unary_expression::do_is_constant() const
else if (this->op_ == OPERATOR_AND)
{
// Taking the address of a variable is constant if it is a
- // global variable, not constant otherwise. In other cases
- // taking the address is probably not a constant.
+ // global variable, not constant otherwise. In other cases taking the
+ // address is probably not a constant.
Var_expression* ve = this->expr_->var_expression();
if (ve != NULL)
{
@@ -4151,58 +4205,40 @@ Unary_expression::do_get_tree(Translate_
{
Temporary_statement* temp = sut->temporary();
Bvariable* bvar = temp->get_backend_variable(context);
- tree var_tree = var_to_tree(bvar);
- Expression* val = sut->expression();
- tree val_tree = val->get_tree(context);
- if (var_tree == error_mark_node || val_tree == error_mark_node)
- return error_mark_node;
- tree addr_tree = build_fold_addr_expr_loc(loc.gcc_location(),
- var_tree);
- return build2_loc(loc.gcc_location(), COMPOUND_EXPR,
- TREE_TYPE(addr_tree),
- build2_loc(sut->location().gcc_location(),
- MODIFY_EXPR, void_type_node,
- var_tree, val_tree),
- addr_tree);
+ Bexpression* bvar_expr = gogo->backend()->var_expression(bvar, loc);
+
+ Expression* val = sut->expression();
+ Bexpression* bval = tree_to_expr(val->get_tree(context));
+
+ Bstatement* bassign =
+ gogo->backend()->assignment_statement(bvar_expr, bval, loc);
+ Bexpression* bvar_addr =
+ gogo->backend()->address_expression(bvar_expr, loc);
+ Bexpression* ret =
+ gogo->backend()->compound_expression(bassign, bvar_addr, loc);
+ return expr_to_tree(ret);
}
}
+ Bexpression* ret;
tree expr = this->expr_->get_tree(context);
- if (expr == error_mark_node)
- return error_mark_node;
-
+ Bexpression* bexpr = tree_to_expr(expr);
+ Btype* btype = this->expr_->type()->get_backend(gogo);
switch (this->op_)
{
case OPERATOR_PLUS:
- return expr;
+ ret = bexpr;
+ break;
case OPERATOR_MINUS:
- {
- tree type = TREE_TYPE(expr);
- tree compute_type = excess_precision_type(type);
- if (compute_type != NULL_TREE)
- expr = ::convert(compute_type, expr);
- tree ret = fold_build1_loc(loc.gcc_location(), NEGATE_EXPR,
- (compute_type != NULL_TREE
- ? compute_type
- : type),
- expr);
- if (compute_type != NULL_TREE)
- ret = ::convert(type, ret);
- return ret;
- }
+ ret = gogo->backend()->unary_expression(this->op_, bexpr, loc);
+ ret = gogo->backend()->convert_expression(btype, ret, loc);
+ break;
case OPERATOR_NOT:
- if (TREE_CODE(TREE_TYPE(expr)) == BOOLEAN_TYPE)
- return fold_build1_loc(loc.gcc_location(), TRUTH_NOT_EXPR,
- TREE_TYPE(expr), expr);
- else
- return fold_build2_loc(loc.gcc_location(), NE_EXPR, boolean_type_node,
- expr, build_int_cst(TREE_TYPE(expr), 0));
-
case OPERATOR_XOR:
- return fold_build1_loc(loc.gcc_location(), BIT_NOT_EXPR, TREE_TYPE(expr),
- expr);
+ ret = gogo->backend()->unary_expression(this->op_, bexpr, loc);
+ break;
case OPERATOR_AND:
if (!this->create_temp_)
@@ -4211,127 +4247,91 @@ Unary_expression::do_get_tree(Translate_
// where we would see one should have been moved onto the
// heap at parse time. Taking the address of a nonconstant
// constructor will not do what the programmer expects.
- go_assert(TREE_CODE(expr) != CONSTRUCTOR || TREE_CONSTANT(expr));
- go_assert(TREE_CODE(expr) != ADDR_EXPR);
+
+ go_assert(!this->expr_->is_composite_literal()
+ || this->expr_->is_immutable());
+ Unary_expression* ue = static_cast<Unary_expression*>(this->expr_);
+ go_assert(ue == NULL || ue->op() != OPERATOR_AND);
}
// Build a decl for a constant constructor.
- if (TREE_CODE(expr) == CONSTRUCTOR && TREE_CONSTANT(expr))
- {
- tree decl = build_decl(this->location().gcc_location(), VAR_DECL,
- create_tmp_var_name("C"), TREE_TYPE(expr));
- DECL_EXTERNAL(decl) = 0;
- TREE_PUBLIC(decl) = 0;
- TREE_READONLY(decl) = 1;
- TREE_CONSTANT(decl) = 1;
- TREE_STATIC(decl) = 1;
- TREE_ADDRESSABLE(decl) = 1;
- DECL_ARTIFICIAL(decl) = 1;
- DECL_INITIAL(decl) = expr;
- rest_of_decl_compilation(decl, 1, 0);
- expr = decl;
- }
-
- if (this->create_temp_
- && !TREE_ADDRESSABLE(TREE_TYPE(expr))
- && (TREE_CODE(expr) == CONST_DECL || !DECL_P(expr))
- && TREE_CODE(expr) != INDIRECT_REF
- && TREE_CODE(expr) != COMPONENT_REF)
- {
- if (current_function_decl != NULL)
- {
- tree tmp = create_tmp_var(TREE_TYPE(expr), get_name(expr));
- DECL_IGNORED_P(tmp) = 1;
- DECL_INITIAL(tmp) = expr;
- TREE_ADDRESSABLE(tmp) = 1;
- return build2_loc(loc.gcc_location(), COMPOUND_EXPR,
- build_pointer_type(TREE_TYPE(expr)),
- build1_loc(loc.gcc_location(), DECL_EXPR,
- void_type_node, tmp),
- build_fold_addr_expr_loc(loc.gcc_location(),
- tmp));
- }
- else
- {
- tree tmp = build_decl(loc.gcc_location(), VAR_DECL,
- create_tmp_var_name("A"), TREE_TYPE(expr));
- DECL_EXTERNAL(tmp) = 0;
- TREE_PUBLIC(tmp) = 0;
- TREE_STATIC(tmp) = 1;
- DECL_ARTIFICIAL(tmp) = 1;
- TREE_ADDRESSABLE(tmp) = 1;
- tree make_tmp;
- if (!TREE_CONSTANT(expr))
- make_tmp = fold_build2_loc(loc.gcc_location(), INIT_EXPR,
- void_type_node, tmp, expr);
- else
- {
- TREE_READONLY(tmp) = 1;
- TREE_CONSTANT(tmp) = 1;
- DECL_INITIAL(tmp) = expr;
- make_tmp = NULL_TREE;
- }
- rest_of_decl_compilation(tmp, 1, 0);
- tree addr = build_fold_addr_expr_loc(loc.gcc_location(), tmp);
- if (make_tmp == NULL_TREE)
- return addr;
- return build2_loc(loc.gcc_location(), COMPOUND_EXPR,
- TREE_TYPE(addr), make_tmp, addr);
- }
- }
+ if ((this->expr_->is_composite_literal()
+ || this->expr_->string_expression() != NULL)
+ && this->expr_->is_immutable())
+ {
+ static unsigned int counter;
+ char buf[100];
+ snprintf(buf, sizeof buf, "C%u", counter);
+ ++counter;
+
+ Bvariable* decl =
+ gogo->backend()->immutable_struct(buf, true, false, btype, loc);
+ gogo->backend()->immutable_struct_set_init(decl, buf, true, false,
+ btype, loc, bexpr);
+ bexpr = gogo->backend()->var_expression(decl, loc);
+ }
- return build_fold_addr_expr_loc(loc.gcc_location(), expr);
+ go_assert(!this->create_temp_ || this->expr_->is_variable());
+ ret = gogo->backend()->address_expression(bexpr, loc);
+ break;
case OPERATOR_MULT:
{
- go_assert(POINTER_TYPE_P(TREE_TYPE(expr)));
+ go_assert(this->expr_->type()->points_to() != NULL);
// If we are dereferencing the pointer to a large struct, we
// need to check for nil. We don't bother to check for small
// structs because we expect the system to crash on a nil
// pointer dereference. However, if we know the address of this
// expression is being taken, we must always check for nil.
- tree target_type_tree = TREE_TYPE(TREE_TYPE(expr));
- if (!VOID_TYPE_P(target_type_tree))
+
+ Type* ptype = this->expr_->type()->points_to();
+ Btype* pbtype = ptype->get_backend(gogo);
+ if (!ptype->is_void_type())
{
- HOST_WIDE_INT s = int_size_in_bytes(target_type_tree);
- if (s == -1 || s >= 4096 || this->issue_nil_check_)
+ size_t s = gogo->backend()->type_size(pbtype);
+ if (s >= 4096 || this->issue_nil_check_)
{
- if (!DECL_P(expr))
- expr = save_expr(expr);
- tree compare = fold_build2_loc(loc.gcc_location(), EQ_EXPR,
- boolean_type_node,
- expr,
- fold_convert(TREE_TYPE(expr),
- null_pointer_node));
+ go_assert(this->expr_->is_variable());
+
+ Expression* nil_expr = Expression::make_nil(loc);
+ Bexpression* nil = tree_to_expr(nil_expr->get_tree(context));
+ Bexpression* compare =
+ gogo->backend()->binary_expression(OPERATOR_EQEQ, bexpr,
+ nil, loc);
+
Expression* crash_expr =
gogo->runtime_error(RUNTIME_ERROR_NIL_DEREFERENCE, loc);
- tree crash = crash_expr->get_tree(context);
- expr = fold_build2_loc(loc.gcc_location(), COMPOUND_EXPR,
- TREE_TYPE(expr), build3(COND_EXPR,
- void_type_node,
- compare, crash,
- NULL_TREE),
- expr);
+ Bexpression* crash =
+ tree_to_expr(crash_expr->get_tree(context));
+ bexpr = gogo->backend()->conditional_expression(btype, compare,
+ crash, bexpr,
+ loc);
+
}
}
// If the type of EXPR is a recursive pointer type, then we
// need to insert a cast before indirecting.
- if (VOID_TYPE_P(target_type_tree))
- {
- Type* pt = this->expr_->type()->points_to();
- tree ind = type_to_tree(pt->get_backend(gogo));
- expr = fold_convert_loc(loc.gcc_location(),
+ tree expr = expr_to_tree(bexpr);
+ tree target_type_tree = TREE_TYPE(TREE_TYPE(expr));
+ if (VOID_TYPE_P(target_type_tree))
+ {
+ tree ind = type_to_tree(pbtype);
+ expr = fold_convert_loc(loc.gcc_location(),
build_pointer_type(ind), expr);
- }
+ bexpr = tree_to_expr(expr);
+ }
- return build_fold_indirect_ref_loc(loc.gcc_location(), expr);
+ ret = gogo->backend()->indirect_expression(bexpr, false, loc);
}
+ break;
default:
go_unreachable();
}
+
+ return expr_to_tree(ret);
}
// Export a unary expression.
@@ -12232,6 +12232,9 @@ class Struct_construction_expression : p
int
do_traverse(Traverse* traverse);
+ bool
+ do_is_immutable() const;
+
Type*
do_type()
{ return this->type_; }
@@ -12334,6 +12337,23 @@ Struct_construction_expression::is_const
return true;
}
+// Return whether this struct is immutable.
+
+bool
+Struct_construction_expression::do_is_immutable() const
+{
+ if (this->vals_ == NULL)
+ return true;
+ for (Expression_list::const_iterator pv = this->vals_->begin();
+ pv != this->vals_->end();
+ ++pv)
+ {
+ if (*pv != NULL && !(*pv)->is_immutable())
+ return false;
+ }
+ return true;
+}
+
// Final type determination.
void
@@ -12546,6 +12566,9 @@ protected:
int
do_traverse(Traverse* traverse);
+ bool
+ do_is_immutable() const;
+
Type*
do_type()
{ return this->type_; }
@@ -12624,6 +12647,23 @@ Array_construction_expression::is_consta
return true;
}
+// Return whether this is an immutable array initializer.
+
+bool
+Array_construction_expression::do_is_immutable() const
+{
+ if (this->vals_ == NULL)
+ return true;
+ for (Expression_list::const_iterator pv = this->vals_->begin();
+ pv != this->vals_->end();
+ ++pv)
+ {
+ if (*pv != NULL && !(*pv)->is_immutable())
+ return false;
+ }
+ return true;
+}
+
// Final type determination.
void
@@ -14390,6 +14430,10 @@ class Type_descriptor_expression : publi
do_type()
{ return Type::make_type_descriptor_ptr_type(); }
+ bool
+ do_is_immutable() const
+ { return true; }
+
void
do_determine_type(const Type_context*)
{ }
Index: gcc/go/gofrontend/expressions.h
===================================================================
--- gcc/go/gofrontend/expressions.h (revision 206904)
+++ gcc/go/gofrontend/expressions.h (working copy)
@@ -403,6 +403,11 @@ class Expression
is_constant() const
{ return this->do_is_constant(); }
+ // Return whether this is an immutable expression.
+ bool
+ is_immutable() const
+ { return this->do_is_immutable(); }
+
// If this is not a numeric constant, return false. If it is one,
// return true, and set VAL to hold the value.
bool
@@ -758,6 +763,11 @@ class Expression
do_is_constant() const
{ return false; }
+ // Return whether this is an immutable expression.
+ virtual bool
+ do_is_immutable() const
+ { return false; }
+
// Return whether this is a constant expression of numeric type, and
// set the Numeric_constant to the value.
virtual bool
@@ -1196,6 +1206,10 @@ class String_expression : public Express
{ return true; }
bool
+ do_is_immutable() const
+ { return true; }
+
+ bool
do_string_constant_value(std::string* val) const
{
*val = this->val_;
Index: gcc/go/gofrontend/backend.h
===================================================================
--- gcc/go/gofrontend/backend.h (revision 206904)
+++ gcc/go/gofrontend/backend.h (working copy)
@@ -298,6 +298,12 @@ class Backend
Bexpression* then_expr, Bexpression* else_expr,
Location) = 0;
+ // Return an expression for the unary operation OP EXPR.
+ // Supported values of OP are (from operators.h):
+ // MINUS, NOT, XOR.
+ virtual Bexpression*
+ unary_expression(Operator op, Bexpression* expr, Location) = 0;
+
// Return an expression for the binary operation LEFT OP RIGHT.
// Supported values of OP are (from operators.h):
// EQEQ, NOTEQ, LT, LE, GT, GE, PLUS, MINUS, OR, XOR, MULT, DIV, MOD,
Index: gcc/go/go-gcc.cc
===================================================================
--- gcc/go/go-gcc.cc (revision 206904)
+++ gcc/go/go-gcc.cc (working copy)
@@ -254,6 +254,9 @@ class Gcc_backend : public Backend
Location);
Bexpression*
+ unary_expression(Operator, Bexpression*, Location);
+
+ Bexpression*
binary_expression(Operator, Bexpression*, Bexpression*, Location);
// Statements.
@@ -1081,6 +1084,47 @@ Gcc_backend::conditional_expression(Btyp
return this->make_expression(ret);
}
+// Return an expression for the unary operation OP EXPR.
+
+Bexpression*
+Gcc_backend::unary_expression(Operator op, Bexpression* expr, Location location)
+{
+ tree expr_tree = expr->get_tree();
+ if (expr_tree == error_mark_node
+ || TREE_TYPE(expr_tree) == error_mark_node)
+ return this->error_expression();
+
+ tree type_tree = TREE_TYPE(expr_tree);
+ enum tree_code code;
+ switch (op)
+ {
+ case OPERATOR_MINUS:
+ {
+ tree computed_type = excess_precision_type(type_tree);
+ if (computed_type != NULL_TREE)
+ {
+ expr_tree = convert(computed_type, expr_tree);
+ type_tree = computed_type;
+ }
+ code = NEGATE_EXPR;
+ break;
+ }
+ case OPERATOR_NOT:
+ code = TRUTH_NOT_EXPR;
+ break;
+ case OPERATOR_XOR:
+ code = BIT_NOT_EXPR;
+ break;
+ default:
+ gcc_unreachable();
+ break;
+ }
+
+ tree ret = fold_build1_loc(location.gcc_location(), code, type_tree,
+ expr_tree);
+ return this->make_expression(ret);
+}
+
// Convert a gofrontend operator to an equivalent tree_code.
static enum tree_code
