From 67a546ab451541e24dae5c8ecbaf692c8cd89f08 Mon Sep 17 00:00:00 2001
From: Ian Lance Taylor <ian@gcc.gnu.org>
Date: Tue, 14 Jul 2015 01:22:25 +0000
Subject: [PATCH] compiler,runtime: Determine if allocations need new pointers
in runtime.
As the removed comment states, if the package being compiled played
certain tricks with pointers that looked like integers, the compiler
might allocate space for new pointers unnecessarily. Since the type
information on the heap is now precise, this logic can be moved to the
runtime.
Reviewed-on: https://go-review.googlesource.com/11581
From-SVN: r225757
---
gcc/go/gofrontend/MERGE | 2 +-
gcc/go/gofrontend/gogo.cc | 10 +---------
gcc/go/gofrontend/runtime.def | 4 ----
libgo/runtime/go-new.c | 11 ++---------
4 files changed, 4 insertions(+), 23 deletions(-)
diff --git a/gcc/go/gofrontend/MERGE b/gcc/go/gofrontend/MERGE
index b524ce11ba53..9a5a2f9df504 100644
--- a/gcc/go/gofrontend/MERGE
+++ b/gcc/go/gofrontend/MERGE
@@ -1,4 +1,4 @@
-83191e8e2cb9f47f7c1e6bcb9997f21163292612
+2c985e4781691fea3eb4171de85265bfbc4e4997
The first line of this file holds the git revision number of the last
merge done from the gofrontend repository.
diff --git a/gcc/go/gofrontend/gogo.cc b/gcc/go/gofrontend/gogo.cc
index 5906b447e15e..ad4672ffe059 100644
--- a/gcc/go/gofrontend/gogo.cc
+++ b/gcc/go/gofrontend/gogo.cc
@@ -4391,15 +4391,7 @@ Gogo::allocate_memory(Type* type, Location location)
Expression* td = Expression::make_type_descriptor(type, location);
Expression* size =
Expression::make_type_info(type, Expression::TYPE_INFO_SIZE);
-
- // If this package imports unsafe, then it may play games with
- // pointers that look like integers. We should be able to determine
- // whether or not to use new pointers in libgo/go-new.c. FIXME.
- bool use_new_pointers = this->imported_unsafe_ || type->has_pointer();
- return Runtime::make_call((use_new_pointers
- ? Runtime::NEW
- : Runtime::NEW_NOPOINTERS),
- location, 2, td, size);
+ return Runtime::make_call(Runtime::NEW, location, 2, td, size);
}
// Traversal class used to check for return statements.
diff --git a/gcc/go/gofrontend/runtime.def b/gcc/go/gofrontend/runtime.def
index 43025dd7b61c..2e79263a632d 100644
--- a/gcc/go/gofrontend/runtime.def
+++ b/gcc/go/gofrontend/runtime.def
@@ -223,10 +223,6 @@ DEF_GO_RUNTIME(REGISTER_GC_ROOTS, "__go_register_gc_roots", P1(POINTER), R0())
// Allocate memory.
DEF_GO_RUNTIME(NEW, "__go_new", P2(TYPE, UINTPTR), R1(POINTER))
-// Allocate memory which can not contain pointers.
-DEF_GO_RUNTIME(NEW_NOPOINTERS, "__go_new_nopointers", P2(TYPE, UINTPTR), R1(POINTER))
-
-
// Start a new goroutine.
DEF_GO_RUNTIME(GO, "__go_go", P2(FUNC_PTR, POINTER), R0())
diff --git a/libgo/runtime/go-new.c b/libgo/runtime/go-new.c
index dad6efb30c0c..01bc2af31211 100644
--- a/libgo/runtime/go-new.c
+++ b/libgo/runtime/go-new.c
@@ -8,19 +8,12 @@
#include "runtime.h"
#include "arch.h"
#include "malloc.h"
+#include "go-type.h"
void *
__go_new (const struct __go_type_descriptor *td, uintptr_t size)
{
return runtime_mallocgc (size,
(uintptr) td | TypeInfo_SingleObject,
- 0);
-}
-
-void *
-__go_new_nopointers (const struct __go_type_descriptor *td, uintptr_t size)
-{
- return runtime_mallocgc (size,
- (uintptr) td | TypeInfo_SingleObject,
- FlagNoScan);
+ td->__code & GO_NO_POINTERS ? FlagNoScan : 0);
}
--
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