Re: Tweak region overflow check

["H.J. Lu" <hjl dot tools at gmail dot com>]

Hi Nathan,

This doesn't work on Linux/Intel64:

http://sourceware.org/bugzilla/show_bug.cgi?id=6475


H.J.
On Thu, Apr 24, 2008 at 2:53 AM, Nathan Sidwell <nathan@codesourcery.com> wrote:
> This patch fixes a problem with region overflow checking on bss-style ALLOC
> but !LOAD sections.  When such sections have an explicitly set LMA, as one
> might have with:
>    .data {...} >ram AT>rom
>    .bss {...} >ram AT>rom
>  we shouldn't test whether they overflow the LMA region, for they will
> occupy no space there.
>
>  One could not override the bss section's LMA region, I suppose, but that
> might be confusing. And I for one find it aesthetically unpleasing to have
> .data and .bss differ in such a manner.
>
>  ok?
>
>  nathan
>  --
>  Nathan Sidwell    ::   http://www.codesourcery.com   ::
> CodeSourcery
>
>
> 2008-04-23  Nathan Sidwell  <nathan@codesourcery.com>
>
>         * ldlang.c (lang_size_sections_1): Don't check LMA overflow on
>         non-load sections.
>
>         * ld-scripts/rgn-over.exp: Allow -ok file names to pass.
>         * ld-scripts/rgn-over8.s: New.
>         * ld-scripts/rgn-over8.t: New.
>         * ld-scripts/rgn-over8-ok.d: New.
>
>  Index: ldlang.c
>  ===================================================================
>  RCS file: /cvs/src/src/ld/ldlang.c,v
>  retrieving revision 1.283
>  diff -c -3 -p -r1.283 ldlang.c
>  *** ldlang.c    22 Feb 2008 14:19:43 -0000      1.283
>  --- ldlang.c    23 Apr 2008 20:56:10 -0000
>  *************** lang_size_sections_1
>  *** 4699,4705 ****
>                   os_region_check (os, os->region, os->addr_tree,
>                                    os->bfd_section->vma);
>
>  !               if (os->lma_region != NULL && os->lma_region != os->region)
>                   {
>                     os->lma_region->current
>                       = os->bfd_section->lma + TO_ADDR
> (os->bfd_section->size);
>  --- 4699,4706 ----
>                   os_region_check (os, os->region, os->addr_tree,
>                                    os->bfd_section->vma);
>
>  !               if (os->lma_region != NULL && os->lma_region != os->region
>  !                   && (os->bfd_section->flags & SEC_LOAD))
>                   {
>                     os->lma_region->current
>                       = os->bfd_section->lma + TO_ADDR
> (os->bfd_section->size);
>  Index: testsuite/ld-scripts/rgn-over.exp
>  ===================================================================
>  RCS file: /cvs/src/src/ld/testsuite/ld-scripts/rgn-over.exp,v
>  retrieving revision 1.2
>  diff -c -3 -p -r1.2 rgn-over.exp
>  *** testsuite/ld-scripts/rgn-over.exp   14 Dec 2007 21:54:50 -0000      1.2
>  --- testsuite/ld-scripts/rgn-over.exp   23 Apr 2008 20:56:13 -0000
>  *************** foreach test_file $test_list {
>  *** 36,52 ****
>       verbose $test_name
>       run_dump_test $test_name
>
>  !     set testname "[file tail $test_name] (map check)"
>  !     if [file exists $map_file] {
>  !       # compare the map file to the expectations in the .d file
>  !       # (run_dump_test can't do that).
>  !       if [regexp_diff $map_file $test_file] {
>  !           fail $testname
>         } else {
>  !           pass $testname
>         }
>  -     } else {
>  -       untested $testname
>       }
>   }
>   set LDFLAGS $old_ldflags
>  --- 36,54 ----
>       verbose $test_name
>       run_dump_test $test_name
>
>  !     if { ! [regexp ".*-ok.d" $test_file] } {
>  !       set testname "[file tail $test_name] (map check)"
>  !       if [file exists $map_file] {
>  !           # compare the map file to the expectations in the .d file
>  !           # (run_dump_test can't do that).
>  !           if [regexp_diff $map_file $test_file] {
>  !               fail $testname
>  !           } else {
>  !               pass $testname
>  !           }
>         } else {
>  !           untested $testname
>         }
>       }
>   }
>   set LDFLAGS $old_ldflags
>  Index: testsuite/ld-scripts/rgn-over8-ok.d
>  ===================================================================
>  RCS file: testsuite/ld-scripts/rgn-over8-ok.d
>  diff -N testsuite/ld-scripts/rgn-over8-ok.d
>  *** /dev/null   1 Jan 1970 00:00:00 -0000
>  --- testsuite/ld-scripts/rgn-over8-ok.d 23 Apr 2008 20:56:13 -0000
>  ***************
>  *** 0 ****
>  --- 1,12 ----
>  + # name: rgn-over8
>  + # source: rgn-over8.s
>  + # ld: -T rgn-over8.t
>  + # objdump: -w -h
>  +
>  + .*:     file format .*
>  +
>  + Sections:
>  + Idx +Name +Size +VMA +LMA +File off +Algn +Flags
>  +   0 .text         0+0000400  0+0000000  0+0000000  [0-9a-f]+  2\*\*0
> CONTENTS, ALLOC, LOAD, READONLY, CODE
>  +   1 .data         0+0000400  0+0001000  0+0000400  [0-9a-f]+  2\*\*0
> CONTENTS, ALLOC, LOAD, DATA
>  +   2 .bss          0+0000400  0+0001400  0+0000800  [0-9a-f]+  2\*\*0
> ALLOC
>  Index: testsuite/ld-scripts/rgn-over8.s
>  ===================================================================
>  RCS file: testsuite/ld-scripts/rgn-over8.s
>  diff -N testsuite/ld-scripts/rgn-over8.s
>  *** /dev/null   1 Jan 1970 00:00:00 -0000
>  --- testsuite/ld-scripts/rgn-over8.s    23 Apr 2008 20:56:13 -0000
>  ***************
>  *** 0 ****
>  --- 1,7 ----
>  +       .text
>  +       .globl main
>  +       .zero 1024
>  +       .data
>  +       .zero 1024
>  +       .bss
>  +       .zero 1024
>  Index: testsuite/ld-scripts/rgn-over8.t
>  ===================================================================
>  RCS file: testsuite/ld-scripts/rgn-over8.t
>  diff -N testsuite/ld-scripts/rgn-over8.t
>  *** /dev/null   1 Jan 1970 00:00:00 -0000
>  --- testsuite/ld-scripts/rgn-over8.t    23 Apr 2008 20:56:13 -0000
>  ***************
>  *** 0 ****
>  --- 1,13 ----
>  + /* Memory region overflow tests: bss to LMA doesn't cause overflow.  */
>  +
>  + MEMORY {
>  +   rom (rwx) : ORIGIN = 0, LENGTH = 2048
>  +   ram (rwx) : ORIGIN = 0x1000, LENGTH = 2048
>  + }
>  + _start = 0x0;
>  + SECTIONS {
>  +   .text : { *(.text) } >rom AT>rom
>  +   .data : { *(.data) } >ram AT>rom
>  +   .bss : { *(.bss) } >ram AT>rom
>  +   /DISCARD/ : { *(*) }
>  + }
>
>