From 554fd8c5195424bdbcabf5de30fdc183aba391bd Mon Sep 17 00:00:00 2001 From: upstream source tree Date: Sun, 15 Mar 2015 20:14:05 -0400 Subject: obtained gcc-4.6.4.tar.bz2 from upstream website; verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository. --- gcc/ada/s-memory-mingw.adb | 221 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 221 insertions(+) create mode 100644 gcc/ada/s-memory-mingw.adb (limited to 'gcc/ada/s-memory-mingw.adb') diff --git a/gcc/ada/s-memory-mingw.adb b/gcc/ada/s-memory-mingw.adb new file mode 100644 index 000000000..31fe0d8a0 --- /dev/null +++ b/gcc/ada/s-memory-mingw.adb @@ -0,0 +1,221 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME COMPONENTS -- +-- -- +-- S Y S T E M . M E M O R Y -- +-- -- +-- B o d y -- +-- -- +-- Copyright (C) 2001-2009, Free Software Foundation, Inc. -- +-- -- +-- GNAT is free software; you can redistribute it and/or modify it under -- +-- terms of the GNU General Public License as published by the Free Soft- -- +-- ware Foundation; either version 3, or (at your option) any later ver- -- +-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- +-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- +-- or FITNESS FOR A PARTICULAR PURPOSE. -- +-- -- +-- As a special exception under Section 7 of GPL version 3, you are granted -- +-- additional permissions described in the GCC Runtime Library Exception, -- +-- version 3.1, as published by the Free Software Foundation. -- +-- -- +-- You should have received a copy of the GNU General Public License and -- +-- a copy of the GCC Runtime Library Exception along with this program; -- +-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- +-- . -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- Extensive contributions were provided by Ada Core Technologies Inc. -- +-- -- +------------------------------------------------------------------------------ + +-- This version provides ways to limit the amount of used memory for systems +-- that do not have OS support for that. + +-- The amount of available memory available for dynamic allocation is limited +-- by setting the environment variable GNAT_MEMORY_LIMIT to the number of +-- kilobytes that can be used. +-- +-- Windows is currently using this version. + +with Ada.Exceptions; +with System.Soft_Links; + +package body System.Memory is + + use Ada.Exceptions; + use System.Soft_Links; + + function c_malloc (Size : size_t) return System.Address; + pragma Import (C, c_malloc, "malloc"); + + procedure c_free (Ptr : System.Address); + pragma Import (C, c_free, "free"); + + function c_realloc + (Ptr : System.Address; Size : size_t) return System.Address; + pragma Import (C, c_realloc, "realloc"); + + function msize (Ptr : System.Address) return size_t; + pragma Import (C, msize, "_msize"); + + function getenv (Str : String) return System.Address; + pragma Import (C, getenv); + + function atoi (Str : System.Address) return Integer; + pragma Import (C, atoi); + + Available_Memory : size_t := 0; + -- Amount of memory that is available for heap allocations. + -- A value of 0 means that the amount is not yet initialized. + + Msize_Accuracy : constant := 4096; + -- Defines the amount of memory to add to requested allocation sizes, + -- because malloc may return a bigger block than requested. As msize + -- is used when by Free, it must be used on allocation as well. To + -- prevent underflow of available_memory we need to use a reserve. + + procedure Check_Available_Memory (Size : size_t); + -- This routine must be called while holding the task lock. When the + -- memory limit is not yet initialized, it will be set to the value of + -- the GNAT_MEMORY_LIMIT environment variable or to unlimited if that + -- does not exist. If the size is larger than the amount of available + -- memory, the task lock will be freed and a storage_error exception + -- will be raised. + + ----------- + -- Alloc -- + ----------- + + function Alloc (Size : size_t) return System.Address is + Result : System.Address; + Actual_Size : size_t := Size; + + begin + if Size = size_t'Last then + Raise_Exception (Storage_Error'Identity, "object too large"); + end if; + + -- Change size from zero to non-zero. We still want a proper pointer + -- for the zero case because pointers to zero length objects have to + -- be distinct, but we can't just go ahead and allocate zero bytes, + -- since some malloc's return zero for a zero argument. + + if Size = 0 then + Actual_Size := 1; + end if; + + Lock_Task.all; + + if Actual_Size + Msize_Accuracy >= Available_Memory then + Check_Available_Memory (Size + Msize_Accuracy); + end if; + + Result := c_malloc (Actual_Size); + + if Result /= System.Null_Address then + Available_Memory := Available_Memory - msize (Result); + end if; + + Unlock_Task.all; + + if Result = System.Null_Address then + Raise_Exception (Storage_Error'Identity, "heap exhausted"); + end if; + + return Result; + end Alloc; + + ---------------------------- + -- Check_Available_Memory -- + ---------------------------- + + procedure Check_Available_Memory (Size : size_t) is + Gnat_Memory_Limit : System.Address; + + begin + if Available_Memory = 0 then + + -- The amount of available memory hasn't been initialized yet + + Gnat_Memory_Limit := getenv ("GNAT_MEMORY_LIMIT" & ASCII.NUL); + + if Gnat_Memory_Limit /= System.Null_Address then + Available_Memory := + size_t (atoi (Gnat_Memory_Limit)) * 1024 + Msize_Accuracy; + else + Available_Memory := size_t'Last; + end if; + end if; + + if Size >= Available_Memory then + + -- There is a memory overflow + + Unlock_Task.all; + Raise_Exception + (Storage_Error'Identity, "heap memory limit exceeded"); + end if; + end Check_Available_Memory; + + ---------- + -- Free -- + ---------- + + procedure Free (Ptr : System.Address) is + begin + Lock_Task.all; + + if Ptr /= System.Null_Address then + Available_Memory := Available_Memory + msize (Ptr); + end if; + + c_free (Ptr); + + Unlock_Task.all; + end Free; + + ------------- + -- Realloc -- + ------------- + + function Realloc + (Ptr : System.Address; + Size : size_t) + return System.Address + is + Result : System.Address; + Actual_Size : constant size_t := Size; + Old_Size : size_t; + + begin + if Size = size_t'Last then + Raise_Exception (Storage_Error'Identity, "object too large"); + end if; + + Lock_Task.all; + + Old_Size := msize (Ptr); + + -- Conservative check - no need to try to be precise here + + if Size + Msize_Accuracy >= Available_Memory then + Check_Available_Memory (Size + Msize_Accuracy); + end if; + + Result := c_realloc (Ptr, Actual_Size); + + if Result /= System.Null_Address then + Available_Memory := Available_Memory + Old_Size - msize (Result); + end if; + + Unlock_Task.all; + + if Result = System.Null_Address then + Raise_Exception (Storage_Error'Identity, "heap exhausted"); + end if; + + return Result; + end Realloc; + +end System.Memory; -- cgit v1.2.3