compiler: permit inlining constant expressions and expression statements
This relatively minor change increases the number of inlinable
functions/methods in the standard library from 983 to 2179.
In particular it permits inlining math/bits/RotateLeftNN. This
restores the speed of crypto/sha256 back to what it was before the
update to 1.13beta1.
Change-Id: I5a1c68ab602a090b02a9e78e45ba813d4f7f8c5b
Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/194340
Reviewed-by: Than McIntosh <thanm@google.com>
diff --git a/go/expressions.cc b/go/expressions.cc
index cb09ec0..7d8963e 100644
--- a/go/expressions.cc
+++ b/go/expressions.cc
@@ -3283,6 +3283,10 @@
Bexpression*
do_get_backend(Translate_context* context);
+ int
+ do_inlining_cost() const
+ { return 1; }
+
// When exporting a reference to a const as part of a const
// expression, we export the value. We ignore the fact that it has
// a name.
diff --git a/go/statements.cc b/go/statements.cc
index 27c309e..3dc394a 100644
--- a/go/statements.cc
+++ b/go/statements.cc
@@ -158,6 +158,10 @@
return Goto_statement::do_import(ifb, loc);
Expression* lhs = Expression::import_expression(ifb, loc);
+
+ if (ifb->match_c_string(" //"))
+ return Statement::make_statement(lhs, true);
+
ifb->require_c_string(" = ");
Expression* rhs = Expression::import_expression(ifb, loc);
return Statement::make_assignment(lhs, rhs, loc);
@@ -2089,6 +2093,14 @@
return true;
}
+// Export an expression statement.
+
+void
+Expression_statement::do_export_statement(Export_function_body* efb)
+{
+ this->expr_->export_expression(efb);
+}
+
// Convert to backend representation.
Bstatement*
diff --git a/go/statements.h b/go/statements.h
index 311bbaa..f1c6be9 100644
--- a/go/statements.h
+++ b/go/statements.h
@@ -924,6 +924,13 @@
bool
do_may_fall_through() const;
+ int
+ do_inlining_cost()
+ { return 0; }
+
+ void
+ do_export_statement(Export_function_body*);
+
Bstatement*
do_get_backend(Translate_context* context);
