* [PATCH v4] i386: Allow -mlarge-data-threshold with -mcmodel=large @ 2023-08-01 19:51 Fangrui Song 2023-08-22 7:19 ` Fangrui Song 2023-10-16 17:12 ` Uros Bizjak 0 siblings, 2 replies; 9+ messages in thread From: Fangrui Song @ 2023-08-01 19:51 UTC (permalink / raw) To: gcc-patches, Florian Weimer, H.J. Lu, Jan Beulich, Jan Hubicka, Michael Matz, Uros Bizjak Cc: Fangrui Song When using -mcmodel=medium, large data objects larger than the -mlarge-data-threshold threshold are placed into large data sections (.lrodata, .ldata, .lbss and some variants). GNU ld and ld.lld 17 place .l* sections into separate output sections. If small and medium code model object files are mixed, the .l* sections won't exert relocation overflow pressure on sections in object files built with -mcmodel=small. However, when using -mcmodel=large, -mlarge-data-threshold doesn't apply. This means that the .rodata/.data/.bss sections may exert relocation overflow pressure on sections in -mcmodel=small object files. This patch allows -mcmodel=large to generate .l* sections and drops an unneeded documentation restriction that the value must be the same. Link: https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU ("Large data sections for the large code model") Signed-off-by: Fangrui Song <maskray@google.com> --- Changes from v1 (https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616947.html): * Clarify commit message. Add link to https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU Changes from v2 * Drop an uneeded limitation in the documentation. Changes from v3 * Change scan-assembler directives to use \. to match literal . --- gcc/config/i386/i386.cc | 15 +++++++++------ gcc/config/i386/i386.opt | 2 +- gcc/doc/invoke.texi | 6 +++--- gcc/testsuite/gcc.target/i386/large-data.c | 13 +++++++++++++ 4 files changed, 26 insertions(+), 10 deletions(-) create mode 100644 gcc/testsuite/gcc.target/i386/large-data.c diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc index eabc70011ea..37e810cc741 100644 --- a/gcc/config/i386/i386.cc +++ b/gcc/config/i386/i386.cc @@ -647,7 +647,8 @@ ix86_can_inline_p (tree caller, tree callee) static bool ix86_in_large_data_p (tree exp) { - if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC) + if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC && + ix86_cmodel != CM_LARGE && ix86_cmodel != CM_LARGE_PIC) return false; if (exp == NULL_TREE) @@ -858,8 +859,9 @@ x86_elf_aligned_decl_common (FILE *file, tree decl, const char *name, unsigned HOST_WIDE_INT size, unsigned align) { - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) - && size > (unsigned int)ix86_section_threshold) + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC || + ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && + size > (unsigned int)ix86_section_threshold) { switch_to_section (get_named_section (decl, ".lbss", 0)); fputs (LARGECOMM_SECTION_ASM_OP, file); @@ -879,9 +881,10 @@ void x86_output_aligned_bss (FILE *file, tree decl, const char *name, unsigned HOST_WIDE_INT size, unsigned align) { - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) - && size > (unsigned int)ix86_section_threshold) - switch_to_section (get_named_section (decl, ".lbss", 0)); + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC || + ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && + size > (unsigned int)ix86_section_threshold) + switch_to_section(get_named_section(decl, ".lbss", 0)); else switch_to_section (bss_section); ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT)); diff --git a/gcc/config/i386/i386.opt b/gcc/config/i386/i386.opt index 1cc8563477a..52fad492353 100644 --- a/gcc/config/i386/i386.opt +++ b/gcc/config/i386/i386.opt @@ -282,7 +282,7 @@ Branches are this expensive (arbitrary units). mlarge-data-threshold= Target RejectNegative Joined UInteger Var(ix86_section_threshold) Init(DEFAULT_LARGE_SECTION_THRESHOLD) --mlarge-data-threshold=<number> Data greater than given threshold will go into .ldata section in x86-64 medium model. +-mlarge-data-threshold=<number> Data greater than given threshold will go into a large data section in x86-64 medium and large code models. mcmodel= Target RejectNegative Joined Enum(cmodel) Var(ix86_cmodel) Init(CM_32) diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 104766f446d..bf6fe3e1a20 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -33207,9 +33207,9 @@ the cache line size. @samp{compat} is the default. @opindex mlarge-data-threshold @item -mlarge-data-threshold=@var{threshold} -When @option{-mcmodel=medium} is specified, data objects larger than -@var{threshold} are placed in the large data section. This value must be the -same across all objects linked into the binary, and defaults to 65535. +When @option{-mcmodel=medium} or @option{-mcmodel=large} is specified, data +objects larger than @var{threshold} are placed in large data sections. The +default is 65535. @opindex mrtd @item -mrtd diff --git a/gcc/testsuite/gcc.target/i386/large-data.c b/gcc/testsuite/gcc.target/i386/large-data.c new file mode 100644 index 00000000000..bdd4acd30b8 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/large-data.c @@ -0,0 +1,13 @@ +/* { dg-do compile } */ +/* { dg-require-effective-target lp64 } */ +/* { dg-options "-O2 -mcmodel=large -mlarge-data-threshold=4" } */ +/* { dg-final { scan-assembler {\.lbss} } } */ +/* { dg-final { scan-assembler {\.bss} } } */ +/* { dg-final { scan-assembler {\.ldata} } } */ +/* { dg-final { scan-assembler {\.data} } } */ +/* { dg-final { scan-assembler {\.lrodata} } } */ +/* { dg-final { scan-assembler {\.rodata} } } */ + +const char rodata_a[] = "abc", rodata_b[] = "abcd"; +char data_a[4] = {1}, data_b[5] = {1}; +char bss_a[4], bss_b[5]; -- 2.41.0.585.gd2178a4bd4-goog ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v4] i386: Allow -mlarge-data-threshold with -mcmodel=large 2023-08-01 19:51 [PATCH v4] i386: Allow -mlarge-data-threshold with -mcmodel=large Fangrui Song @ 2023-08-22 7:19 ` Fangrui Song 2023-09-13 18:19 ` Fangrui Song 2023-10-16 17:12 ` Uros Bizjak 1 sibling, 1 reply; 9+ messages in thread From: Fangrui Song @ 2023-08-22 7:19 UTC (permalink / raw) To: gcc-patches, Florian Weimer, H.J. Lu, Jan Beulich, Jan Hubicka, Michael Matz, Uros Bizjak On Tue, Aug 1, 2023 at 12:51 PM Fangrui Song <maskray@google.com> wrote: > > When using -mcmodel=medium, large data objects larger than the > -mlarge-data-threshold threshold are placed into large data sections > (.lrodata, .ldata, .lbss and some variants). GNU ld and ld.lld 17 place > .l* sections into separate output sections. If small and medium code > model object files are mixed, the .l* sections won't exert relocation > overflow pressure on sections in object files built with -mcmodel=small. > > However, when using -mcmodel=large, -mlarge-data-threshold doesn't > apply. This means that the .rodata/.data/.bss sections may exert > relocation overflow pressure on sections in -mcmodel=small object files. > > This patch allows -mcmodel=large to generate .l* sections and drops an > unneeded documentation restriction that the value must be the same. > > Link: https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > ("Large data sections for the large code model") > > Signed-off-by: Fangrui Song <maskray@google.com> > > --- > Changes from v1 (https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616947.html): > * Clarify commit message. Add link to https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > > Changes from v2 > * Drop an uneeded limitation in the documentation. > > Changes from v3 > * Change scan-assembler directives to use \. to match literal . > --- > gcc/config/i386/i386.cc | 15 +++++++++------ > gcc/config/i386/i386.opt | 2 +- > gcc/doc/invoke.texi | 6 +++--- > gcc/testsuite/gcc.target/i386/large-data.c | 13 +++++++++++++ > 4 files changed, 26 insertions(+), 10 deletions(-) > create mode 100644 gcc/testsuite/gcc.target/i386/large-data.c > > [...] Ping:) ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v4] i386: Allow -mlarge-data-threshold with -mcmodel=large 2023-08-22 7:19 ` Fangrui Song @ 2023-09-13 18:19 ` Fangrui Song 2023-09-27 17:54 ` Fangrui Song 0 siblings, 1 reply; 9+ messages in thread From: Fangrui Song @ 2023-09-13 18:19 UTC (permalink / raw) To: gcc-patches, Florian Weimer, H.J. Lu, Jan Beulich, Jan Hubicka, Michael Matz, Uros Bizjak On Tue, Aug 22, 2023 at 12:19 AM Fangrui Song <maskray@google.com> wrote: > > On Tue, Aug 1, 2023 at 12:51 PM Fangrui Song <maskray@google.com> wrote: > > > > When using -mcmodel=medium, large data objects larger than the > > -mlarge-data-threshold threshold are placed into large data sections > > (.lrodata, .ldata, .lbss and some variants). GNU ld and ld.lld 17 place > > .l* sections into separate output sections. If small and medium code > > model object files are mixed, the .l* sections won't exert relocation > > overflow pressure on sections in object files built with -mcmodel=small. > > > > However, when using -mcmodel=large, -mlarge-data-threshold doesn't > > apply. This means that the .rodata/.data/.bss sections may exert > > relocation overflow pressure on sections in -mcmodel=small object files. > > > > This patch allows -mcmodel=large to generate .l* sections and drops an > > unneeded documentation restriction that the value must be the same. > > > > Link: https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > > ("Large data sections for the large code model") > > > > Signed-off-by: Fangrui Song <maskray@google.com> > > > > --- > > Changes from v1 (https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616947.html): > > * Clarify commit message. Add link to https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > > > > Changes from v2 > > * Drop an uneeded limitation in the documentation. > > > > Changes from v3 > > * Change scan-assembler directives to use \. to match literal . > > --- > > gcc/config/i386/i386.cc | 15 +++++++++------ > > gcc/config/i386/i386.opt | 2 +- > > gcc/doc/invoke.texi | 6 +++--- > > gcc/testsuite/gcc.target/i386/large-data.c | 13 +++++++++++++ > > 4 files changed, 26 insertions(+), 10 deletions(-) > > create mode 100644 gcc/testsuite/gcc.target/i386/large-data.c > > > > [...] > > Ping:) Ping:) https://gcc.gnu.org/pipermail/gcc-patches/2023-August/625993.html (I don't have write access to gcc.) -- 宋方睿 ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v4] i386: Allow -mlarge-data-threshold with -mcmodel=large 2023-09-13 18:19 ` Fangrui Song @ 2023-09-27 17:54 ` Fangrui Song 0 siblings, 0 replies; 9+ messages in thread From: Fangrui Song @ 2023-09-27 17:54 UTC (permalink / raw) To: gcc-patches, Florian Weimer, H.J. Lu, Jan Beulich, Jan Hubicka, Michael Matz, Uros Bizjak On Wed, Sep 13, 2023 at 11:19 AM Fangrui Song <maskray@google.com> wrote: > > On Tue, Aug 22, 2023 at 12:19 AM Fangrui Song <maskray@google.com> wrote: > > > > On Tue, Aug 1, 2023 at 12:51 PM Fangrui Song <maskray@google.com> wrote: > > > > > > When using -mcmodel=medium, large data objects larger than the > > > -mlarge-data-threshold threshold are placed into large data sections > > > (.lrodata, .ldata, .lbss and some variants). GNU ld and ld.lld 17 place > > > .l* sections into separate output sections. If small and medium code > > > model object files are mixed, the .l* sections won't exert relocation > > > overflow pressure on sections in object files built with -mcmodel=small. > > > > > > However, when using -mcmodel=large, -mlarge-data-threshold doesn't > > > apply. This means that the .rodata/.data/.bss sections may exert > > > relocation overflow pressure on sections in -mcmodel=small object files. > > > > > > This patch allows -mcmodel=large to generate .l* sections and drops an > > > unneeded documentation restriction that the value must be the same. > > > > > > Link: https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > > > ("Large data sections for the large code model") > > > > > > Signed-off-by: Fangrui Song <maskray@google.com> > > > > > > --- > > > Changes from v1 (https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616947.html): > > > * Clarify commit message. Add link to https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > > > > > > Changes from v2 > > > * Drop an uneeded limitation in the documentation. > > > > > > Changes from v3 > > > * Change scan-assembler directives to use \. to match literal . > > > --- > > > gcc/config/i386/i386.cc | 15 +++++++++------ > > > gcc/config/i386/i386.opt | 2 +- > > > gcc/doc/invoke.texi | 6 +++--- > > > gcc/testsuite/gcc.target/i386/large-data.c | 13 +++++++++++++ > > > 4 files changed, 26 insertions(+), 10 deletions(-) > > > create mode 100644 gcc/testsuite/gcc.target/i386/large-data.c > > > > > > [...] > > > > Ping:) > > Ping:) https://gcc.gnu.org/pipermail/gcc-patches/2023-August/625993.html > > (I don't have write access to gcc.) > > > -- > 宋方睿 Ping? :) https://gcc.gnu.org/pipermail/gcc-patches/2023-August/625993.html (I don't have write access to gcc.) -- 宋方睿 ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v4] i386: Allow -mlarge-data-threshold with -mcmodel=large 2023-08-01 19:51 [PATCH v4] i386: Allow -mlarge-data-threshold with -mcmodel=large Fangrui Song 2023-08-22 7:19 ` Fangrui Song @ 2023-10-16 17:12 ` Uros Bizjak 2023-10-16 18:24 ` [PATCH v5] " Fangrui Song 1 sibling, 1 reply; 9+ messages in thread From: Uros Bizjak @ 2023-10-16 17:12 UTC (permalink / raw) To: Fangrui Song Cc: gcc-patches, Florian Weimer, H.J. Lu, Jan Beulich, Jan Hubicka, Michael Matz On Tue, Aug 1, 2023 at 9:51 PM Fangrui Song <maskray@google.com> wrote: > > When using -mcmodel=medium, large data objects larger than the > -mlarge-data-threshold threshold are placed into large data sections > (.lrodata, .ldata, .lbss and some variants). GNU ld and ld.lld 17 place > .l* sections into separate output sections. If small and medium code > model object files are mixed, the .l* sections won't exert relocation > overflow pressure on sections in object files built with -mcmodel=small. > > However, when using -mcmodel=large, -mlarge-data-threshold doesn't > apply. This means that the .rodata/.data/.bss sections may exert > relocation overflow pressure on sections in -mcmodel=small object files. > > This patch allows -mcmodel=large to generate .l* sections and drops an > unneeded documentation restriction that the value must be the same. > > Link: https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > ("Large data sections for the large code model") > > Signed-off-by: Fangrui Song <maskray@google.com> > > --- > Changes from v1 (https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616947.html): > * Clarify commit message. Add link to https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > > Changes from v2 > * Drop an uneeded limitation in the documentation. > > Changes from v3 > * Change scan-assembler directives to use \. to match literal . > --- > gcc/config/i386/i386.cc | 15 +++++++++------ > gcc/config/i386/i386.opt | 2 +- > gcc/doc/invoke.texi | 6 +++--- > gcc/testsuite/gcc.target/i386/large-data.c | 13 +++++++++++++ > 4 files changed, 26 insertions(+), 10 deletions(-) > create mode 100644 gcc/testsuite/gcc.target/i386/large-data.c > > diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc > index eabc70011ea..37e810cc741 100644 > --- a/gcc/config/i386/i386.cc > +++ b/gcc/config/i386/i386.cc > @@ -647,7 +647,8 @@ ix86_can_inline_p (tree caller, tree callee) > static bool > ix86_in_large_data_p (tree exp) > { > - if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC) > + if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC && > + ix86_cmodel != CM_LARGE && ix86_cmodel != CM_LARGE_PIC) Please split multi-line expression before the operator, not after it, as instructed in GNU Coding Standards [1] ... [1] https://www.gnu.org/prep/standards/html_node/Formatting.html > return false; > > if (exp == NULL_TREE) > @@ -858,8 +859,9 @@ x86_elf_aligned_decl_common (FILE *file, tree decl, > const char *name, unsigned HOST_WIDE_INT size, > unsigned align) > { > - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) > - && size > (unsigned int)ix86_section_threshold) > + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC || > + ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && > + size > (unsigned int)ix86_section_threshold) ... also here ... > { > switch_to_section (get_named_section (decl, ".lbss", 0)); > fputs (LARGECOMM_SECTION_ASM_OP, file); > @@ -879,9 +881,10 @@ void > x86_output_aligned_bss (FILE *file, tree decl, const char *name, > unsigned HOST_WIDE_INT size, unsigned align) > { > - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) > - && size > (unsigned int)ix86_section_threshold) > - switch_to_section (get_named_section (decl, ".lbss", 0)); > + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC || > + ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && > + size > (unsigned int)ix86_section_threshold) ... and here. OK with these formatting changes. Thanks, Uros. > + switch_to_section(get_named_section(decl, ".lbss", 0)); > else > switch_to_section (bss_section); > ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT)); > diff --git a/gcc/config/i386/i386.opt b/gcc/config/i386/i386.opt > index 1cc8563477a..52fad492353 100644 > --- a/gcc/config/i386/i386.opt > +++ b/gcc/config/i386/i386.opt > @@ -282,7 +282,7 @@ Branches are this expensive (arbitrary units). > > mlarge-data-threshold= > Target RejectNegative Joined UInteger Var(ix86_section_threshold) Init(DEFAULT_LARGE_SECTION_THRESHOLD) > --mlarge-data-threshold=<number> Data greater than given threshold will go into .ldata section in x86-64 medium model. > +-mlarge-data-threshold=<number> Data greater than given threshold will go into a large data section in x86-64 medium and large code models. > > mcmodel= > Target RejectNegative Joined Enum(cmodel) Var(ix86_cmodel) Init(CM_32) > diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi > index 104766f446d..bf6fe3e1a20 100644 > --- a/gcc/doc/invoke.texi > +++ b/gcc/doc/invoke.texi > @@ -33207,9 +33207,9 @@ the cache line size. @samp{compat} is the default. > > @opindex mlarge-data-threshold > @item -mlarge-data-threshold=@var{threshold} > -When @option{-mcmodel=medium} is specified, data objects larger than > -@var{threshold} are placed in the large data section. This value must be the > -same across all objects linked into the binary, and defaults to 65535. > +When @option{-mcmodel=medium} or @option{-mcmodel=large} is specified, data > +objects larger than @var{threshold} are placed in large data sections. The > +default is 65535. > > @opindex mrtd > @item -mrtd > diff --git a/gcc/testsuite/gcc.target/i386/large-data.c b/gcc/testsuite/gcc.target/i386/large-data.c > new file mode 100644 > index 00000000000..bdd4acd30b8 > --- /dev/null > +++ b/gcc/testsuite/gcc.target/i386/large-data.c > @@ -0,0 +1,13 @@ > +/* { dg-do compile } */ > +/* { dg-require-effective-target lp64 } */ > +/* { dg-options "-O2 -mcmodel=large -mlarge-data-threshold=4" } */ > +/* { dg-final { scan-assembler {\.lbss} } } */ > +/* { dg-final { scan-assembler {\.bss} } } */ > +/* { dg-final { scan-assembler {\.ldata} } } */ > +/* { dg-final { scan-assembler {\.data} } } */ > +/* { dg-final { scan-assembler {\.lrodata} } } */ > +/* { dg-final { scan-assembler {\.rodata} } } */ > + > +const char rodata_a[] = "abc", rodata_b[] = "abcd"; > +char data_a[4] = {1}, data_b[5] = {1}; > +char bss_a[4], bss_b[5]; > -- > 2.41.0.585.gd2178a4bd4-goog > ^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v5] i386: Allow -mlarge-data-threshold with -mcmodel=large 2023-10-16 17:12 ` Uros Bizjak @ 2023-10-16 18:24 ` Fangrui Song 2023-10-16 19:10 ` Uros Bizjak 0 siblings, 1 reply; 9+ messages in thread From: Fangrui Song @ 2023-10-16 18:24 UTC (permalink / raw) To: Uros Bizjak Cc: gcc-patches, Florian Weimer, H.J. Lu, Jan Beulich, Jan Hubicka, Michael Matz On 2023-10-16, Uros Bizjak wrote: >On Tue, Aug 1, 2023 at 9:51 PM Fangrui Song <maskray@google.com> wrote: >> >> When using -mcmodel=medium, large data objects larger than the >> -mlarge-data-threshold threshold are placed into large data sections >> (.lrodata, .ldata, .lbss and some variants). GNU ld and ld.lld 17 place >> .l* sections into separate output sections. If small and medium code >> model object files are mixed, the .l* sections won't exert relocation >> overflow pressure on sections in object files built with -mcmodel=small. >> >> However, when using -mcmodel=large, -mlarge-data-threshold doesn't >> apply. This means that the .rodata/.data/.bss sections may exert >> relocation overflow pressure on sections in -mcmodel=small object files. >> >> This patch allows -mcmodel=large to generate .l* sections and drops an >> unneeded documentation restriction that the value must be the same. >> >> Link: https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU >> ("Large data sections for the large code model") >> >> Signed-off-by: Fangrui Song <maskray@google.com> >> >> --- >> Changes from v1 (https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616947.html): >> * Clarify commit message. Add link to https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU >> >> Changes from v2 >> * Drop an uneeded limitation in the documentation. >> >> Changes from v3 >> * Change scan-assembler directives to use \. to match literal . >> --- >> gcc/config/i386/i386.cc | 15 +++++++++------ >> gcc/config/i386/i386.opt | 2 +- >> gcc/doc/invoke.texi | 6 +++--- >> gcc/testsuite/gcc.target/i386/large-data.c | 13 +++++++++++++ >> 4 files changed, 26 insertions(+), 10 deletions(-) >> create mode 100644 gcc/testsuite/gcc.target/i386/large-data.c >> >> diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc >> index eabc70011ea..37e810cc741 100644 >> --- a/gcc/config/i386/i386.cc >> +++ b/gcc/config/i386/i386.cc >> @@ -647,7 +647,8 @@ ix86_can_inline_p (tree caller, tree callee) >> static bool >> ix86_in_large_data_p (tree exp) >> { >> - if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC) >> + if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC && >> + ix86_cmodel != CM_LARGE && ix86_cmodel != CM_LARGE_PIC) > >Please split multi-line expression before the operator, not after it, >as instructed in GNU Coding Standards [1] ... > >[1] https://www.gnu.org/prep/standards/html_node/Formatting.html > >> return false; >> >> if (exp == NULL_TREE) >> @@ -858,8 +859,9 @@ x86_elf_aligned_decl_common (FILE *file, tree decl, >> const char *name, unsigned HOST_WIDE_INT size, >> unsigned align) >> { >> - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) >> - && size > (unsigned int)ix86_section_threshold) >> + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC || >> + ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && >> + size > (unsigned int)ix86_section_threshold) > >... also here ... > >> { >> switch_to_section (get_named_section (decl, ".lbss", 0)); >> fputs (LARGECOMM_SECTION_ASM_OP, file); >> @@ -879,9 +881,10 @@ void >> x86_output_aligned_bss (FILE *file, tree decl, const char *name, >> unsigned HOST_WIDE_INT size, unsigned align) >> { >> - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) >> - && size > (unsigned int)ix86_section_threshold) >> - switch_to_section (get_named_section (decl, ".lbss", 0)); >> + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC || >> + ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && >> + size > (unsigned int)ix86_section_threshold) > >... and here. > >OK with these formatting changes. > >Thanks, >Uros. Thank you for the review! Posted PATCH v5 https://gcc.gnu.org/pipermail/gcc-patches/2023-October/633153.html with the formatting. I don't have write access to the gcc repository:) (Hmmm... in emacs, C-c . gnu RET C-M-\ doesn't fix the && || formatting errors.) >> + switch_to_section(get_named_section(decl, ".lbss", 0)); >> else >> switch_to_section (bss_section); >> ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT)); >> diff --git a/gcc/config/i386/i386.opt b/gcc/config/i386/i386.opt >> index 1cc8563477a..52fad492353 100644 >> --- a/gcc/config/i386/i386.opt >> +++ b/gcc/config/i386/i386.opt >> @@ -282,7 +282,7 @@ Branches are this expensive (arbitrary units). >> >> mlarge-data-threshold= >> Target RejectNegative Joined UInteger Var(ix86_section_threshold) Init(DEFAULT_LARGE_SECTION_THRESHOLD) >> --mlarge-data-threshold=<number> Data greater than given threshold will go into .ldata section in x86-64 medium model. >> +-mlarge-data-threshold=<number> Data greater than given threshold will go into a large data section in x86-64 medium and large code models. >> >> mcmodel= >> Target RejectNegative Joined Enum(cmodel) Var(ix86_cmodel) Init(CM_32) >> diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi >> index 104766f446d..bf6fe3e1a20 100644 >> --- a/gcc/doc/invoke.texi >> +++ b/gcc/doc/invoke.texi >> @@ -33207,9 +33207,9 @@ the cache line size. @samp{compat} is the default. >> >> @opindex mlarge-data-threshold >> @item -mlarge-data-threshold=@var{threshold} >> -When @option{-mcmodel=medium} is specified, data objects larger than >> -@var{threshold} are placed in the large data section. This value must be the >> -same across all objects linked into the binary, and defaults to 65535. >> +When @option{-mcmodel=medium} or @option{-mcmodel=large} is specified, data >> +objects larger than @var{threshold} are placed in large data sections. The >> +default is 65535. >> >> @opindex mrtd >> @item -mrtd >> diff --git a/gcc/testsuite/gcc.target/i386/large-data.c b/gcc/testsuite/gcc.target/i386/large-data.c >> new file mode 100644 >> index 00000000000..bdd4acd30b8 >> --- /dev/null >> +++ b/gcc/testsuite/gcc.target/i386/large-data.c >> @@ -0,0 +1,13 @@ >> +/* { dg-do compile } */ >> +/* { dg-require-effective-target lp64 } */ >> +/* { dg-options "-O2 -mcmodel=large -mlarge-data-threshold=4" } */ >> +/* { dg-final { scan-assembler {\.lbss} } } */ >> +/* { dg-final { scan-assembler {\.bss} } } */ >> +/* { dg-final { scan-assembler {\.ldata} } } */ >> +/* { dg-final { scan-assembler {\.data} } } */ >> +/* { dg-final { scan-assembler {\.lrodata} } } */ >> +/* { dg-final { scan-assembler {\.rodata} } } */ >> + >> +const char rodata_a[] = "abc", rodata_b[] = "abcd"; >> +char data_a[4] = {1}, data_b[5] = {1}; >> +char bss_a[4], bss_b[5]; >> -- >> 2.41.0.585.gd2178a4bd4-goog >> From da49445a50c57b583201e3fb48fa91781b9ec761 Mon Sep 17 00:00:00 2001 From: Fangrui Song <maskray@google.com> Date: Thu, 27 Apr 2023 12:29:31 -0700 Subject: [PATCH v5] i386: Allow -mlarge-data-threshold with -mcmodel=large When using -mcmodel=medium, large data objects larger than the -mlarge-data-threshold threshold are placed into large data sections (.lrodata, .ldata, .lbss and some variants). GNU ld and ld.lld 17 place .l* sections into separate output sections. If small and medium code model object files are mixed, the .l* sections won't exert relocation overflow pressure on sections in object files built with -mcmodel=small. However, when using -mcmodel=large, -mlarge-data-threshold doesn't apply. This means that the .rodata/.data/.bss sections may exert relocation overflow pressure on sections in -mcmodel=small object files. This patch allows -mcmodel=large to generate .l* sections and drops an unneeded documentation restriction that the value must be the same. Link: https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU ("Large data sections for the large code model") Signed-off-by: Fangrui Song <maskray@google.com> --- Changes from v1 (https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616947.html): * Clarify commit message. Add link to https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU Changes from v2 * Drop an uneeded limitation in the documentation. Changes from v3 * Change scan-assembler directives to use \. to match literal . Changes from v4 (https://gcc.gnu.org/pipermail/gcc-patches/2023-October/633145.html) * "When you split an expression into multiple lines, split it before an operator, not after one." --- gcc/config/i386/i386.cc | 9 ++++++--- gcc/config/i386/i386.opt | 2 +- gcc/doc/invoke.texi | 6 +++--- gcc/testsuite/gcc.target/i386/large-data.c | 13 +++++++++++++ 4 files changed, 23 insertions(+), 7 deletions(-) create mode 100644 gcc/testsuite/gcc.target/i386/large-data.c diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc index 8251b67e2d6..641e7680335 100644 --- a/gcc/config/i386/i386.cc +++ b/gcc/config/i386/i386.cc @@ -663,7 +663,8 @@ ix86_can_inline_p (tree caller, tree callee) static bool ix86_in_large_data_p (tree exp) { - if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC) + if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC + && ix86_cmodel != CM_LARGE && ix86_cmodel != CM_LARGE_PIC) return false; if (exp == NULL_TREE) @@ -874,7 +875,8 @@ x86_elf_aligned_decl_common (FILE *file, tree decl, const char *name, unsigned HOST_WIDE_INT size, unsigned align) { - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC + || ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && size > (unsigned int)ix86_section_threshold) { switch_to_section (get_named_section (decl, ".lbss", 0)); @@ -895,7 +897,8 @@ void x86_output_aligned_bss (FILE *file, tree decl, const char *name, unsigned HOST_WIDE_INT size, unsigned align) { - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC + || ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && size > (unsigned int)ix86_section_threshold) switch_to_section (get_named_section (decl, ".lbss", 0)); else diff --git a/gcc/config/i386/i386.opt b/gcc/config/i386/i386.opt index b8382c48099..0c3b8f4b621 100644 --- a/gcc/config/i386/i386.opt +++ b/gcc/config/i386/i386.opt @@ -282,7 +282,7 @@ Branches are this expensive (arbitrary units). mlarge-data-threshold= Target RejectNegative Joined UInteger Var(ix86_section_threshold) Init(DEFAULT_LARGE_SECTION_THRESHOLD) --mlarge-data-threshold=<number> Data greater than given threshold will go into .ldata section in x86-64 medium model. +-mlarge-data-threshold=<number> Data greater than given threshold will go into a large data section in x86-64 medium and large code models. mcmodel= Target RejectNegative Joined Enum(cmodel) Var(ix86_cmodel) Init(CM_32) diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index eb714d18511..50745a3a195 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -33390,9 +33390,9 @@ the cache line size. @samp{compat} is the default. @opindex mlarge-data-threshold @item -mlarge-data-threshold=@var{threshold} -When @option{-mcmodel=medium} is specified, data objects larger than -@var{threshold} are placed in the large data section. This value must be the -same across all objects linked into the binary, and defaults to 65535. +When @option{-mcmodel=medium} or @option{-mcmodel=large} is specified, data +objects larger than @var{threshold} are placed in large data sections. The +default is 65535. @opindex mrtd @item -mrtd diff --git a/gcc/testsuite/gcc.target/i386/large-data.c b/gcc/testsuite/gcc.target/i386/large-data.c new file mode 100644 index 00000000000..bdd4acd30b8 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/large-data.c @@ -0,0 +1,13 @@ +/* { dg-do compile } */ +/* { dg-require-effective-target lp64 } */ +/* { dg-options "-O2 -mcmodel=large -mlarge-data-threshold=4" } */ +/* { dg-final { scan-assembler {\.lbss} } } */ +/* { dg-final { scan-assembler {\.bss} } } */ +/* { dg-final { scan-assembler {\.ldata} } } */ +/* { dg-final { scan-assembler {\.data} } } */ +/* { dg-final { scan-assembler {\.lrodata} } } */ +/* { dg-final { scan-assembler {\.rodata} } } */ + +const char rodata_a[] = "abc", rodata_b[] = "abcd"; +char data_a[4] = {1}, data_b[5] = {1}; +char bss_a[4], bss_b[5]; -- 2.42.0.655.g421f12c284-goog ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v5] i386: Allow -mlarge-data-threshold with -mcmodel=large 2023-10-16 18:24 ` [PATCH v5] " Fangrui Song @ 2023-10-16 19:10 ` Uros Bizjak 2023-10-16 19:58 ` Fangrui Song 0 siblings, 1 reply; 9+ messages in thread From: Uros Bizjak @ 2023-10-16 19:10 UTC (permalink / raw) To: Fangrui Song Cc: gcc-patches, Florian Weimer, H.J. Lu, Jan Beulich, Jan Hubicka, Michael Matz On Mon, Oct 16, 2023 at 8:24 PM Fangrui Song <maskray@google.com> wrote: > > On 2023-10-16, Uros Bizjak wrote: > >On Tue, Aug 1, 2023 at 9:51 PM Fangrui Song <maskray@google.com> wrote: > >> > >> When using -mcmodel=medium, large data objects larger than the > >> -mlarge-data-threshold threshold are placed into large data sections > >> (.lrodata, .ldata, .lbss and some variants). GNU ld and ld.lld 17 place > >> .l* sections into separate output sections. If small and medium code > >> model object files are mixed, the .l* sections won't exert relocation > >> overflow pressure on sections in object files built with -mcmodel=small. > >> > >> However, when using -mcmodel=large, -mlarge-data-threshold doesn't > >> apply. This means that the .rodata/.data/.bss sections may exert > >> relocation overflow pressure on sections in -mcmodel=small object files. > >> > >> This patch allows -mcmodel=large to generate .l* sections and drops an > >> unneeded documentation restriction that the value must be the same. > >> > >> Link: https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > >> ("Large data sections for the large code model") > >> > >> Signed-off-by: Fangrui Song <maskray@google.com> > >> > >> --- > >> Changes from v1 (https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616947.html): > >> * Clarify commit message. Add link to https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > >> > >> Changes from v2 > >> * Drop an uneeded limitation in the documentation. > >> > >> Changes from v3 > >> * Change scan-assembler directives to use \. to match literal . > >> --- > >> gcc/config/i386/i386.cc | 15 +++++++++------ > >> gcc/config/i386/i386.opt | 2 +- > >> gcc/doc/invoke.texi | 6 +++--- > >> gcc/testsuite/gcc.target/i386/large-data.c | 13 +++++++++++++ > >> 4 files changed, 26 insertions(+), 10 deletions(-) > >> create mode 100644 gcc/testsuite/gcc.target/i386/large-data.c > >> > >> diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc > >> index eabc70011ea..37e810cc741 100644 > >> --- a/gcc/config/i386/i386.cc > >> +++ b/gcc/config/i386/i386.cc > >> @@ -647,7 +647,8 @@ ix86_can_inline_p (tree caller, tree callee) > >> static bool > >> ix86_in_large_data_p (tree exp) > >> { > >> - if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC) > >> + if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC && > >> + ix86_cmodel != CM_LARGE && ix86_cmodel != CM_LARGE_PIC) > > > >Please split multi-line expression before the operator, not after it, > >as instructed in GNU Coding Standards [1] ... > > > >[1] https://www.gnu.org/prep/standards/html_node/Formatting.html > > > >> return false; > >> > >> if (exp == NULL_TREE) > >> @@ -858,8 +859,9 @@ x86_elf_aligned_decl_common (FILE *file, tree decl, > >> const char *name, unsigned HOST_WIDE_INT size, > >> unsigned align) > >> { > >> - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) > >> - && size > (unsigned int)ix86_section_threshold) > >> + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC || > >> + ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && > >> + size > (unsigned int)ix86_section_threshold) > > > >... also here ... > > > >> { > >> switch_to_section (get_named_section (decl, ".lbss", 0)); > >> fputs (LARGECOMM_SECTION_ASM_OP, file); > >> @@ -879,9 +881,10 @@ void > >> x86_output_aligned_bss (FILE *file, tree decl, const char *name, > >> unsigned HOST_WIDE_INT size, unsigned align) > >> { > >> - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) > >> - && size > (unsigned int)ix86_section_threshold) > >> - switch_to_section (get_named_section (decl, ".lbss", 0)); > >> + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC || > >> + ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && > >> + size > (unsigned int)ix86_section_threshold) > > > >... and here. > > > >OK with these formatting changes. > > > >Thanks, > >Uros. > > Thank you for the review! > Posted PATCH v5 https://gcc.gnu.org/pipermail/gcc-patches/2023-October/633153.html > with the formatting. > > I don't have write access to the gcc repository:) Please provide the ChangeLog entry (see [1,2]) and I'll commit the patch for you. [1] https://gcc.gnu.org/contribute.html [2] https://gcc.gnu.org/codingconventions.html#ChangeLogs Thanks, Uros. ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v5] i386: Allow -mlarge-data-threshold with -mcmodel=large 2023-10-16 19:10 ` Uros Bizjak @ 2023-10-16 19:58 ` Fangrui Song 2023-10-16 21:46 ` Uros Bizjak 0 siblings, 1 reply; 9+ messages in thread From: Fangrui Song @ 2023-10-16 19:58 UTC (permalink / raw) To: Uros Bizjak Cc: gcc-patches, Florian Weimer, H.J. Lu, Jan Beulich, Jan Hubicka, Michael Matz On Mon, Oct 16, 2023 at 12:10 PM Uros Bizjak <ubizjak@gmail.com> wrote: > > On Mon, Oct 16, 2023 at 8:24 PM Fangrui Song <maskray@google.com> wrote: > > > > On 2023-10-16, Uros Bizjak wrote: > > >On Tue, Aug 1, 2023 at 9:51 PM Fangrui Song <maskray@google.com> wrote: > > >> > > >> When using -mcmodel=medium, large data objects larger than the > > >> -mlarge-data-threshold threshold are placed into large data sections > > >> (.lrodata, .ldata, .lbss and some variants). GNU ld and ld.lld 17 place > > >> .l* sections into separate output sections. If small and medium code > > >> model object files are mixed, the .l* sections won't exert relocation > > >> overflow pressure on sections in object files built with -mcmodel=small. > > >> > > >> However, when using -mcmodel=large, -mlarge-data-threshold doesn't > > >> apply. This means that the .rodata/.data/.bss sections may exert > > >> relocation overflow pressure on sections in -mcmodel=small object files. > > >> > > >> This patch allows -mcmodel=large to generate .l* sections and drops an > > >> unneeded documentation restriction that the value must be the same. > > >> > > >> Link: https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > > >> ("Large data sections for the large code model") > > >> > > >> Signed-off-by: Fangrui Song <maskray@google.com> > > >> > > >> --- > > >> Changes from v1 (https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616947.html): > > >> * Clarify commit message. Add link to https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > > >> > > >> Changes from v2 > > >> * Drop an uneeded limitation in the documentation. > > >> > > >> Changes from v3 > > >> * Change scan-assembler directives to use \. to match literal . > > >> --- > > >> gcc/config/i386/i386.cc | 15 +++++++++------ > > >> gcc/config/i386/i386.opt | 2 +- > > >> gcc/doc/invoke.texi | 6 +++--- > > >> gcc/testsuite/gcc.target/i386/large-data.c | 13 +++++++++++++ > > >> 4 files changed, 26 insertions(+), 10 deletions(-) > > >> create mode 100644 gcc/testsuite/gcc.target/i386/large-data.c > > >> > > >> diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc > > >> index eabc70011ea..37e810cc741 100644 > > >> --- a/gcc/config/i386/i386.cc > > >> +++ b/gcc/config/i386/i386.cc > > >> @@ -647,7 +647,8 @@ ix86_can_inline_p (tree caller, tree callee) > > >> static bool > > >> ix86_in_large_data_p (tree exp) > > >> { > > >> - if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC) > > >> + if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC && > > >> + ix86_cmodel != CM_LARGE && ix86_cmodel != CM_LARGE_PIC) > > > > > >Please split multi-line expression before the operator, not after it, > > >as instructed in GNU Coding Standards [1] ... > > > > > >[1] https://www.gnu.org/prep/standards/html_node/Formatting.html > > > > > >> return false; > > >> > > >> if (exp == NULL_TREE) > > >> @@ -858,8 +859,9 @@ x86_elf_aligned_decl_common (FILE *file, tree decl, > > >> const char *name, unsigned HOST_WIDE_INT size, > > >> unsigned align) > > >> { > > >> - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) > > >> - && size > (unsigned int)ix86_section_threshold) > > >> + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC || > > >> + ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && > > >> + size > (unsigned int)ix86_section_threshold) > > > > > >... also here ... > > > > > >> { > > >> switch_to_section (get_named_section (decl, ".lbss", 0)); > > >> fputs (LARGECOMM_SECTION_ASM_OP, file); > > >> @@ -879,9 +881,10 @@ void > > >> x86_output_aligned_bss (FILE *file, tree decl, const char *name, > > >> unsigned HOST_WIDE_INT size, unsigned align) > > >> { > > >> - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) > > >> - && size > (unsigned int)ix86_section_threshold) > > >> - switch_to_section (get_named_section (decl, ".lbss", 0)); > > >> + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC || > > >> + ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && > > >> + size > (unsigned int)ix86_section_threshold) > > > > > >... and here. > > > > > >OK with these formatting changes. > > > > > >Thanks, > > >Uros. > > > > Thank you for the review! > > Posted PATCH v5 https://gcc.gnu.org/pipermail/gcc-patches/2023-October/633153.html > > with the formatting. > > > > I don't have write access to the gcc repository:) > > Please provide the ChangeLog entry (see [1,2]) and I'll commit the > patch for you. > > [1] https://gcc.gnu.org/contribute.html > [2] https://gcc.gnu.org/codingconventions.html#ChangeLogs > > Thanks, > Uros. It's so kind of you! Attached the ChangeLog: gcc/ * config/i386/i386.cc (ix86_can_inline_p): Handle CM_LARGE and CM_LARGE_PIC. (x86_elf_aligned_decl_common): Ditto. (x86_output_aligned_bss): Ditto. * config/i386/i386.opt: Update doc for -mlarge-data-threshold=. * doc/invoke.texi: Update doc for -mlarge-data-threshold=. gcc/testsuite/: * gcc.target/i386/large-data.c: New test. -- 宋方睿 ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v5] i386: Allow -mlarge-data-threshold with -mcmodel=large 2023-10-16 19:58 ` Fangrui Song @ 2023-10-16 21:46 ` Uros Bizjak 0 siblings, 0 replies; 9+ messages in thread From: Uros Bizjak @ 2023-10-16 21:46 UTC (permalink / raw) To: Fangrui Song Cc: gcc-patches, Florian Weimer, H.J. Lu, Jan Beulich, Jan Hubicka, Michael Matz On Mon, Oct 16, 2023 at 9:58 PM Fangrui Song <maskray@google.com> wrote: > > On Mon, Oct 16, 2023 at 12:10 PM Uros Bizjak <ubizjak@gmail.com> wrote: > > > > On Mon, Oct 16, 2023 at 8:24 PM Fangrui Song <maskray@google.com> wrote: > > > > > > On 2023-10-16, Uros Bizjak wrote: > > > >On Tue, Aug 1, 2023 at 9:51 PM Fangrui Song <maskray@google.com> wrote: > > > >> > > > >> When using -mcmodel=medium, large data objects larger than the > > > >> -mlarge-data-threshold threshold are placed into large data sections > > > >> (.lrodata, .ldata, .lbss and some variants). GNU ld and ld.lld 17 place > > > >> .l* sections into separate output sections. If small and medium code > > > >> model object files are mixed, the .l* sections won't exert relocation > > > >> overflow pressure on sections in object files built with -mcmodel=small. > > > >> > > > >> However, when using -mcmodel=large, -mlarge-data-threshold doesn't > > > >> apply. This means that the .rodata/.data/.bss sections may exert > > > >> relocation overflow pressure on sections in -mcmodel=small object files. > > > >> > > > >> This patch allows -mcmodel=large to generate .l* sections and drops an > > > >> unneeded documentation restriction that the value must be the same. > > > >> > > > >> Link: https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > > > >> ("Large data sections for the large code model") > > > >> > > > >> Signed-off-by: Fangrui Song <maskray@google.com> > > > >> > > > >> --- > > > >> Changes from v1 (https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616947.html): > > > >> * Clarify commit message. Add link to https://groups.google.com/g/x86-64-abi/c/jnQdJeabxiU > > > >> > > > >> Changes from v2 > > > >> * Drop an uneeded limitation in the documentation. > > > >> > > > >> Changes from v3 > > > >> * Change scan-assembler directives to use \. to match literal . > > > >> --- > > > >> gcc/config/i386/i386.cc | 15 +++++++++------ > > > >> gcc/config/i386/i386.opt | 2 +- > > > >> gcc/doc/invoke.texi | 6 +++--- > > > >> gcc/testsuite/gcc.target/i386/large-data.c | 13 +++++++++++++ > > > >> 4 files changed, 26 insertions(+), 10 deletions(-) > > > >> create mode 100644 gcc/testsuite/gcc.target/i386/large-data.c > > > >> > > > >> diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc > > > >> index eabc70011ea..37e810cc741 100644 > > > >> --- a/gcc/config/i386/i386.cc > > > >> +++ b/gcc/config/i386/i386.cc > > > >> @@ -647,7 +647,8 @@ ix86_can_inline_p (tree caller, tree callee) > > > >> static bool > > > >> ix86_in_large_data_p (tree exp) > > > >> { > > > >> - if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC) > > > >> + if (ix86_cmodel != CM_MEDIUM && ix86_cmodel != CM_MEDIUM_PIC && > > > >> + ix86_cmodel != CM_LARGE && ix86_cmodel != CM_LARGE_PIC) > > > > > > > >Please split multi-line expression before the operator, not after it, > > > >as instructed in GNU Coding Standards [1] ... > > > > > > > >[1] https://www.gnu.org/prep/standards/html_node/Formatting.html > > > > > > > >> return false; > > > >> > > > >> if (exp == NULL_TREE) > > > >> @@ -858,8 +859,9 @@ x86_elf_aligned_decl_common (FILE *file, tree decl, > > > >> const char *name, unsigned HOST_WIDE_INT size, > > > >> unsigned align) > > > >> { > > > >> - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) > > > >> - && size > (unsigned int)ix86_section_threshold) > > > >> + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC || > > > >> + ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && > > > >> + size > (unsigned int)ix86_section_threshold) > > > > > > > >... also here ... > > > > > > > >> { > > > >> switch_to_section (get_named_section (decl, ".lbss", 0)); > > > >> fputs (LARGECOMM_SECTION_ASM_OP, file); > > > >> @@ -879,9 +881,10 @@ void > > > >> x86_output_aligned_bss (FILE *file, tree decl, const char *name, > > > >> unsigned HOST_WIDE_INT size, unsigned align) > > > >> { > > > >> - if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC) > > > >> - && size > (unsigned int)ix86_section_threshold) > > > >> - switch_to_section (get_named_section (decl, ".lbss", 0)); > > > >> + if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC || > > > >> + ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC) && > > > >> + size > (unsigned int)ix86_section_threshold) > > > > > > > >... and here. > > > > > > > >OK with these formatting changes. > > > > > > > >Thanks, > > > >Uros. > > > > > > Thank you for the review! > > > Posted PATCH v5 https://gcc.gnu.org/pipermail/gcc-patches/2023-October/633153.html > > > with the formatting. > > > > > > I don't have write access to the gcc repository:) > > > > Please provide the ChangeLog entry (see [1,2]) and I'll commit the > > patch for you. > > > > [1] https://gcc.gnu.org/contribute.html > > [2] https://gcc.gnu.org/codingconventions.html#ChangeLogs > > > > Thanks, > > Uros. > > It's so kind of you! Attached the ChangeLog: > > gcc/ > * config/i386/i386.cc (ix86_can_inline_p): > Handle CM_LARGE and CM_LARGE_PIC. > (x86_elf_aligned_decl_common): Ditto. > (x86_output_aligned_bss): Ditto. > * config/i386/i386.opt: Update doc for -mlarge-data-threshold=. > * doc/invoke.texi: Update doc for -mlarge-data-threshold=. > > gcc/testsuite/: > * gcc.target/i386/large-data.c: New test. Committed as [1]. [1] https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=1a64156c7e25813afa8d4d8bbeb0590cad91cf55 Uros. ^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2023-10-16 21:47 UTC | newest] Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2023-08-01 19:51 [PATCH v4] i386: Allow -mlarge-data-threshold with -mcmodel=large Fangrui Song 2023-08-22 7:19 ` Fangrui Song 2023-09-13 18:19 ` Fangrui Song 2023-09-27 17:54 ` Fangrui Song 2023-10-16 17:12 ` Uros Bizjak 2023-10-16 18:24 ` [PATCH v5] " Fangrui Song 2023-10-16 19:10 ` Uros Bizjak 2023-10-16 19:58 ` Fangrui Song 2023-10-16 21:46 ` Uros Bizjak
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).