From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 23459 invoked by alias); 7 May 2012 23:30:37 -0000 Received: (qmail 23449 invoked by uid 22791); 7 May 2012 23:30:34 -0000 X-SWARE-Spam-Status: No, hits=-1.0 required=5.0 tests=AWL,BAYES_00,KAM_STOCKGEN,TW_BJ,TW_JS,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from eddie.linux-mips.org (HELO cvs.linux-mips.org) (78.24.191.182) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 07 May 2012 23:30:17 +0000 Received: from localhost.localdomain ([127.0.0.1]:38351 "EHLO localhost.localdomain" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S1903684Ab2EGXaP (ORCPT ); Tue, 8 May 2012 01:30:15 +0200 Date: Mon, 07 May 2012 23:30:00 -0000 From: "Maciej W. Rozycki" To: binutils@sourceware.org Subject: [PATCH] VAX/BFD: Omit PLT slots for local symbols Message-ID: User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-IsSubscribed: yes Mailing-List: contact binutils-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: binutils-owner@sourceware.org X-SW-Source: 2012-05/txt/msg00085.txt.bz2 Hi, The change below fixes a problem with the creation of the PLT on the VAX target, where entries are made where they should not for local symbols, leading to unneeded or even empty slots. The conditions for the latters are a bit obscure, for such a slot to be created a dynamic symbol has to be preempted in the link with a static hidden symbol referred to by a PLT relocation (i.e. from a PIC relocatable). This is covered by the test case provided. Executables with empty PLT slots are invalid and rejected by the dynamic linker. There is some code duplication in the area affected, so I have merged the two pieces (that deal with local and garbage-collected symbols, respectively) into one, similarly to how some other targets do it. Also the attempt to make a symbol whose h->dynindx is -1 dynamic is incorrect here -- such symbols will have qualified as local in SYMBOL_CALLS_LOCAL and shouldn't be produced. No regressions with this change. OK to apply? 2012-05-08 Maciej W. Rozycki bfd/ * elf32-vax.c (elf_vax_adjust_dynamic_symbol): Don't allocate PLT slots for local symbols. ld/testsuite/ * ld-vax-elf/plt-local-lib.dd: New test. * ld-vax-elf/plt-local-lib.ld: New test linker script. * ld-vax-elf/plt-local-lib.s: New test source. * ld-vax-elf/plt-local.dd: New test. * ld-vax-elf/plt-local.ld:New test linker script. * ld-vax-elf/plt-local.s: New test source. * ld-vax-elf/plt-local-hidden-pic.s: New test source. * ld-vax-elf/plt-local-rehidden-pic.s: New test source. * ld-vax-elf/vax-elf.exp: New test script. Maciej binutils-vax-plt-local.patch Index: binutils/bfd/elf32-vax.c =================================================================== --- binutils.orig/bfd/elf32-vax.c +++ binutils/bfd/elf32-vax.c @@ -934,39 +934,21 @@ elf_vax_adjust_dynamic_symbol (info, h) if (h->type == STT_FUNC || h->needs_plt) { - if (! info->shared - && !h->def_dynamic - && !h->ref_dynamic - /* We must always create the plt entry if it was referenced - by a PLTxxO relocation. In this case we already recorded - it as a dynamic symbol. */ - && h->dynindx == -1) + if (h->plt.refcount <= 0 + || SYMBOL_CALLS_LOCAL (info, h) + || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT + && h->root.type == bfd_link_hash_undefweak)) { /* This case can occur if we saw a PLTxx reloc in an input file, but the symbol was never referred to by a dynamic - object. In such a case, we don't actually need to build - a procedure linkage table, and we can just do a PCxx - reloc instead. */ - BFD_ASSERT (h->needs_plt); + object, or if all references were garbage collected. In + such a case, we don't actually need to build a procedure + linkage table, and we can just do a PCxx reloc instead. */ h->plt.offset = (bfd_vma) -1; - return TRUE; - } - - /* GC may have rendered this entry unused. */ - if (h->plt.refcount <= 0) - { h->needs_plt = 0; - h->plt.offset = (bfd_vma) -1; return TRUE; } - /* Make sure this symbol is output as a dynamic symbol. */ - if (h->dynindx == -1) - { - if (! bfd_elf_link_record_dynamic_symbol (info, h)) - return FALSE; - } - s = bfd_get_section_by_name (dynobj, ".plt"); BFD_ASSERT (s != NULL); Index: binutils/ld/testsuite/ld-vax-elf/plt-local-hidden-pic.s =================================================================== --- /dev/null +++ binutils/ld/testsuite/ld-vax-elf/plt-local-hidden-pic.s @@ -0,0 +1,14 @@ + .text + + .hidden foo_hidden + .globl foo_hidden + .type foo_hidden, @function +foo_hidden: + .word 0 + calls $0, foo_extern + calls $0, foo_global + calls $0, foo_local + calls $0, foo_hidden + calls $0, foo_rehidden + ret + .size foo_hidden, . - foo_hidden Index: binutils/ld/testsuite/ld-vax-elf/plt-local-lib.dd =================================================================== --- /dev/null +++ binutils/ld/testsuite/ld-vax-elf/plt-local-lib.dd @@ -0,0 +1,91 @@ +.*: +file format .*vax.* + +Disassembly of section \.plt: + +00001000 : + 1000: dd ef 76 20 pushl 307c <_GLOBAL_OFFSET_TABLE_\+0x4> + 1004: 00 00 + 1006: 17 ff 74 20 jmp \*3080 <_GLOBAL_OFFSET_TABLE_\+0x8> + 100a: 00 00 + +0000100c : + 100c: fc 0f \.word 0x0ffc # Entry mask: < r11 r10 r9 r8 r7 r6 r5 r4 r3 r2 > + 100e: 16 ef ec ff jsb 1000 + 1012: ff ff + 1014: 00 00 00 00 \.long 0x00000000 + +00001018 : + 1018: fc 0f \.word 0x0ffc # Entry mask: < r11 r10 r9 r8 r7 r6 r5 r4 r3 r2 > + 101a: 16 ef e0 ff jsb 1000 + 101e: ff ff + 1020: 0c 00 00 00 \.long 0x0000000c + +00001024 : + 1024: fc 0f \.word 0x0ffc # Entry mask: < r11 r10 r9 r8 r7 r6 r5 r4 r3 r2 > + 1026: 16 ef d4 ff jsb 1000 + 102a: ff ff + 102c: 18 00 00 00 \.long 0x00000018 + +00001030 : + 1030: fc 0f \.word 0x0ffc # Entry mask: < r11 r10 r9 r8 r7 r6 r5 r4 r3 r2 > + 1032: 16 ef c8 ff jsb 1000 + 1036: ff ff + 1038: 24 00 00 00 \.long 0x00000024 + +Disassembly of section \.text: + +00002000 : + 2000: 00 00 \.word 0x0000 # Entry mask: < > + 2002: fb 00 ff 7f calls \$0x0,\*3088 <_GLOBAL_OFFSET_TABLE_\+0x10> + 2006: 10 00 00 + 2009: fb 00 ff 80 calls \$0x0,\*3090 <_GLOBAL_OFFSET_TABLE_\+0x18> + 200d: 10 00 00 + 2010: fb 00 ff 6d calls \$0x0,\*3084 <_GLOBAL_OFFSET_TABLE_\+0xc> + 2014: 10 00 00 + 2017: fb 00 ef 2e calls \$0x0,204c + 201b: 00 00 00 + 201e: fb 00 ff 67 calls \$0x0,\*308c <_GLOBAL_OFFSET_TABLE_\+0x14> + 2022: 10 00 00 + 2025: 04 ret + +00002026 : + 2026: 00 00 \.word 0x0000 # Entry mask: < > + 2028: fb 00 ff 59 calls \$0x0,\*3088 <_GLOBAL_OFFSET_TABLE_\+0x10> + 202c: 10 00 00 + 202f: fb 00 ff 5a calls \$0x0,\*3090 <_GLOBAL_OFFSET_TABLE_\+0x18> + 2033: 10 00 00 + 2036: fb 00 ff 47 calls \$0x0,\*3084 <_GLOBAL_OFFSET_TABLE_\+0xc> + 203a: 10 00 00 + 203d: fb 00 ef 08 calls \$0x0,204c + 2041: 00 00 00 + 2044: fb 00 ff 41 calls \$0x0,\*308c <_GLOBAL_OFFSET_TABLE_\+0x14> + 2048: 10 00 00 + 204b: 04 ret + +0000204c : + 204c: 00 00 \.word 0x0000 # Entry mask: < > + 204e: fb 00 ff 33 calls \$0x0,\*3088 <_GLOBAL_OFFSET_TABLE_\+0x10> + 2052: 10 00 00 + 2055: fb 00 ff 34 calls \$0x0,\*3090 <_GLOBAL_OFFSET_TABLE_\+0x18> + 2059: 10 00 00 + 205c: fb 00 ff 21 calls \$0x0,\*3084 <_GLOBAL_OFFSET_TABLE_\+0xc> + 2060: 10 00 00 + 2063: fb 00 ef e2 calls \$0x0,204c + 2067: ff ff ff + 206a: fb 00 ff 1b calls \$0x0,\*308c <_GLOBAL_OFFSET_TABLE_\+0x14> + 206e: 10 00 00 + 2071: 04 ret + +00002072 : + 2072: 00 00 \.word 0x0000 # Entry mask: < > + 2074: fb 00 ff 0d calls \$0x0,\*3088 <_GLOBAL_OFFSET_TABLE_\+0x10> + 2078: 10 00 00 + 207b: fb 00 ff 0e calls \$0x0,\*3090 <_GLOBAL_OFFSET_TABLE_\+0x18> + 207f: 10 00 00 + 2082: fb 00 ff fb calls \$0x0,\*3084 <_GLOBAL_OFFSET_TABLE_\+0xc> + 2086: 0f 00 00 + 2089: fb 00 ef bc calls \$0x0,204c + 208d: ff ff ff + 2090: fb 00 ff f5 calls \$0x0,\*308c <_GLOBAL_OFFSET_TABLE_\+0x14> + 2094: 0f 00 00 + 2097: 04 ret Index: binutils/ld/testsuite/ld-vax-elf/plt-local-lib.ld =================================================================== --- /dev/null +++ binutils/ld/testsuite/ld-vax-elf/plt-local-lib.ld @@ -0,0 +1,18 @@ +SECTIONS +{ + . = 0; + .hash : { *(.hash) } + .dynsym : { *(.dynsym) } + .dynstr : { *(.dynstr) } + .rela.plt : { *(.rela.plt) } + + . = 0x1000; + .plt : { *(.plt) } + + . = 0x2000; + .text : { *(.text) } + + . = 0x3000; + .dynamic : { *(.dynamic) } + .got : { *(.got.plt) } +} Index: binutils/ld/testsuite/ld-vax-elf/plt-local-lib.s =================================================================== --- /dev/null +++ binutils/ld/testsuite/ld-vax-elf/plt-local-lib.s @@ -0,0 +1,50 @@ + .text + + .globl foo_extern + .type foo_extern, @function +foo_extern: + .word 0 + calls $0, foo_extern + calls $0, foo_global + calls $0, foo_local + calls $0, foo_hidden + calls $0, foo_rehidden + ret + .size foo_extern, . - foo_extern + + .globl foo_local + .type foo_local, @function +foo_local: + .word 0 + calls $0, foo_extern + calls $0, foo_global + calls $0, foo_local + calls $0, foo_hidden + calls $0, foo_rehidden + ret + .size foo_local, . - foo_local + + .hidden foo_hidden + .globl foo_hidden + .type foo_hidden, @function +foo_hidden: + .word 0 + calls $0, foo_extern + calls $0, foo_global + calls $0, foo_local + calls $0, foo_hidden + calls $0, foo_rehidden + ret + .size foo_hidden, . - foo_hidden + + .globl foo_rehidden + .type foo_rehidden, @function +foo_rehidden: + .word 0 + calls $0, foo_extern + calls $0, foo_global + calls $0, foo_local + calls $0, foo_hidden + calls $0, foo_rehidden + ret + .size foo_rehidden, . - foo_rehidden Index: binutils/ld/testsuite/ld-vax-elf/plt-local-rehidden-pic.s =================================================================== --- /dev/null +++ binutils/ld/testsuite/ld-vax-elf/plt-local-rehidden-pic.s @@ -0,0 +1,14 @@ + .text + + .hidden foo_rehidden + .globl foo_rehidden + .type foo_rehidden, @function +foo_rehidden: + .word 0 + calls $0, foo_extern + calls $0, foo_global + calls $0, foo_local + calls $0, foo_hidden + calls $0, foo_rehidden + ret + .size foo_rehidden, . - foo_rehidden Index: binutils/ld/testsuite/ld-vax-elf/plt-local.dd =================================================================== --- /dev/null +++ binutils/ld/testsuite/ld-vax-elf/plt-local.dd @@ -0,0 +1,73 @@ +.*: +file format .*vax.* + +Disassembly of section \.plt: + +00001000 : + 1000: dd ef 86 20 pushl 308c <_GLOBAL_OFFSET_TABLE_\+0x4> + 1004: 00 00 + 1006: 17 ff 84 20 jmp \*3090 <_GLOBAL_OFFSET_TABLE_\+0x8> + 100a: 00 00 + +0000100c : + 100c: fc 0f \.word 0x0ffc # Entry mask: < r11 r10 r9 r8 r7 r6 r5 r4 r3 r2 > + 100e: 16 ef ec ff jsb 1000 + 1012: ff ff + 1014: 00 00 00 00 \.long 0x00000000 + +Disassembly of section \.text: + +00002000 : + 2000: 00 00 \.word 0x0000 # Entry mask: < > + 2002: fb 00 ff 8b calls \$0x0,\*3094 <_GLOBAL_OFFSET_TABLE_\+0xc> + 2006: 10 00 00 + 2009: fb 00 ef 3c calls \$0x0,204c + 200d: 00 00 00 + 2010: fb 00 ef 5b calls \$0x0,2072 + 2014: 00 00 00 + 2017: fb 00 ef e2 calls \$0x0,2000 + 201b: ff ff ff + 201e: fb 00 ef 01 calls \$0x0,2026 + 2022: 00 00 00 + 2025: 04 ret + +00002026 : + 2026: 00 00 \.word 0x0000 # Entry mask: < > + 2028: fb 00 ff 65 calls \$0x0,\*3094 <_GLOBAL_OFFSET_TABLE_\+0xc> + 202c: 10 00 00 + 202f: fb 00 ef 16 calls \$0x0,204c + 2033: 00 00 00 + 2036: fb 00 ef 35 calls \$0x0,2072 + 203a: 00 00 00 + 203d: fb 00 ef bc calls \$0x0,2000 + 2041: ff ff ff + 2044: fb 00 ef db calls \$0x0,2026 + 2048: ff ff ff + 204b: 04 ret + +0000204c : + 204c: 00 00 \.word 0x0000 # Entry mask: < > + 204e: fb 00 ff 3f calls \$0x0,\*3094 <_GLOBAL_OFFSET_TABLE_\+0xc> + 2052: 10 00 00 + 2055: fb 00 ef f0 calls \$0x0,204c + 2059: ff ff ff + 205c: fb 00 ef 0f calls \$0x0,2072 + 2060: 00 00 00 + 2063: fb 00 ef 96 calls \$0x0,2000 + 2067: ff ff ff + 206a: fb 00 ef b5 calls \$0x0,2026 + 206e: ff ff ff + 2071: 04 ret + +00002072 : + 2072: 00 00 \.word 0x0000 # Entry mask: < > + 2074: fb 00 ff 19 calls \$0x0,\*3094 <_GLOBAL_OFFSET_TABLE_\+0xc> + 2078: 10 00 00 + 207b: fb 00 ef ca calls \$0x0,204c + 207f: ff ff ff + 2082: fb 00 ef e9 calls \$0x0,2072 + 2086: ff ff ff + 2089: fb 00 ef 70 calls \$0x0,2000 + 208d: ff ff ff + 2090: fb 00 ef 8f calls \$0x0,2026 + 2094: ff ff ff + 2097: 04 ret Index: binutils/ld/testsuite/ld-vax-elf/plt-local.ld =================================================================== --- /dev/null +++ binutils/ld/testsuite/ld-vax-elf/plt-local.ld @@ -0,0 +1,34 @@ +ENTRY (foo_global) +SECTIONS +{ + . = 0; + .interp : { *(.interp) } + .hash : { *(.hash) } + .dynsym : { *(.dynsym) } + .dynstr : { *(.dynstr) } + .gnu.version : { *(.gnu.version) } + .gnu.version_d : { *(.gnu.version_d) } + .rela.plt : { *(.rela.plt) } + + . = 0x1000; + .plt : { *(.plt) } + + . = 0x2000; + .text : { *(.text) } + + . = 0x3000; + .dynamic : { *(.dynamic) } + .got : { *(.got.plt) } +}; +VERSION +{ + { + global: + foo_extern; + foo_global; + foo_hidden; + foo_rehidden; + local: + foo_local; + }; +} Index: binutils/ld/testsuite/ld-vax-elf/plt-local.s =================================================================== --- /dev/null +++ binutils/ld/testsuite/ld-vax-elf/plt-local.s @@ -0,0 +1,25 @@ + .text + + .globl foo_global + .type foo_global, @function +foo_global: + .word 0 + calls $0, foo_extern + calls $0, foo_global + calls $0, foo_local + calls $0, foo_hidden + calls $0, foo_rehidden + ret + .size foo_global, . - foo_global + + .globl foo_local + .type foo_local, @function +foo_local: + .word 0 + calls $0, foo_extern + calls $0, foo_global + calls $0, foo_local + calls $0, foo_hidden + calls $0, foo_rehidden + ret + .size foo_local, . - foo_local Index: binutils/ld/testsuite/ld-vax-elf/vax-elf.exp =================================================================== --- /dev/null +++ binutils/ld/testsuite/ld-vax-elf/vax-elf.exp @@ -0,0 +1,50 @@ +# Expect script for VAX ELF linker tests +# Copyright 2012 Free Software Foundation, Inc. +# +# This file is part of the GNU Binutils. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, +# MA 02110-1301, USA. +# + +if { ![istarget vax-*-*] || ![is_elf_format] } { + return +} + +run_ld_link_tests [list \ + [list "PLT test (shared library)" \ + "-shared -T plt-local-lib.ld" \ + "-k" \ + { plt-local-lib.s } \ + { { objdump -d plt-local-lib.dd } } \ + "plt-local-lib.so"] \ + [list "PLT test (object 1)" \ + "-r" \ + "-k" \ + { plt-local-hidden-pic.s } \ + {} \ + "plt-local-hidden-pic-r.o"] \ + [list "PLT test (object 2)" \ + "-r" \ + "-k" \ + { plt-local-rehidden-pic.s } \ + {} \ + "plt-local-rehidden-pic-r.o"] \ + [list "PLT test (executable)" \ + "-T plt-local.ld tmpdir/plt-local-hidden-pic-r.o tmpdir/plt-local-rehidden-pic-r.o tmpdir/plt-local-lib.so" \ + "" \ + { plt-local.s } \ + { { objdump -d plt-local.dd } } \ + "plt-local"]]