| Message ID | 81484c01-87ab-fb43-68c3-2c025c0ddb86@suse.cz |
|---|---|
| State | New |
| Headers | show |
| Series | Come up with section_flag enum. | expand |
PING^1 On 9/7/21 11:43, Martin Liška wrote: > Hi. > > I'm planning some refactoring related to 'section *' and I noticed we have > quite ugly mask definitions (of form 1UL << N), where SECTION_FORGET is unused > and > > #define SECTION_STYLE_MASK 0x600000 /* bits used for SECTION_STYLE */ > > Is actually OR of 2 other values. What about making that a standard enum value > with 1UL << N values? > > Patch can bootstrap on x86_64-linux-gnu and survives regression tests. > > Ready to be installed? > Thanks, > Martin > > gcc/ChangeLog: > > * output.h (enum section_flag): New. > (SECTION_FORGET): Remove. > (SECTION_ENTSIZE): Make it (1UL << 8) - 1. > (SECTION_STYLE_MASK): Define it based on other enum > values. > * varasm.c (switch_to_section): Remove unused handling of > SECTION_FORGET. > --- > gcc/output.h | 85 +++++++++++++++++++++++++++++----------------------- > gcc/varasm.c | 5 +--- > 2 files changed, 48 insertions(+), 42 deletions(-) > > diff --git a/gcc/output.h b/gcc/output.h > index 73ca4545f4f..8f6f15308f4 100644 > --- a/gcc/output.h > +++ b/gcc/output.h > @@ -365,44 +365,53 @@ extern void default_function_switched_text_sections (FILE *, tree, bool); > extern void no_asm_to_stream (FILE *); > > /* Flags controlling properties of a section. */ > -#define SECTION_ENTSIZE 0x000ff /* entity size in section */ > -#define SECTION_CODE 0x00100 /* contains code */ > -#define SECTION_WRITE 0x00200 /* data is writable */ > -#define SECTION_DEBUG 0x00400 /* contains debug data */ > -#define SECTION_LINKONCE 0x00800 /* is linkonce */ > -#define SECTION_SMALL 0x01000 /* contains "small data" */ > -#define SECTION_BSS 0x02000 /* contains zeros only */ > -#define SECTION_FORGET 0x04000 /* forget that we've entered the section */ > -#define SECTION_MERGE 0x08000 /* contains mergeable data */ > -#define SECTION_STRINGS 0x10000 /* contains zero terminated strings without > - embedded zeros */ > -#define SECTION_OVERRIDE 0x20000 /* allow override of default flags */ > -#define SECTION_TLS 0x40000 /* contains thread-local storage */ > -#define SECTION_NOTYPE 0x80000 /* don't output @progbits */ > -#define SECTION_DECLARED 0x100000 /* section has been used */ > -#define SECTION_STYLE_MASK 0x600000 /* bits used for SECTION_STYLE */ > -#define SECTION_COMMON 0x800000 /* contains common data */ > -#define SECTION_RELRO 0x1000000 /* data is readonly after relocation processing */ > -#define SECTION_EXCLUDE 0x2000000 /* discarded by the linker */ > -#define SECTION_RETAIN 0x4000000 /* retained by the linker. */ > -#define SECTION_LINK_ORDER 0x8000000 /* section needs link-order. */ > - > -/* NB: The maximum SECTION_MACH_DEP is 0x10000000 since AVR needs 4 bits > - in SECTION_MACH_DEP. */ > -#define SECTION_MACH_DEP 0x10000000 /* subsequent bits reserved for target */ > - > -/* This SECTION_STYLE is used for unnamed sections that we can switch > - to using a special assembler directive. */ > -#define SECTION_UNNAMED 0x000000 > - > -/* This SECTION_STYLE is used for named sections that we can switch > - to using a general section directive. */ > -#define SECTION_NAMED 0x200000 > - > -/* This SECTION_STYLE is used for sections that we cannot switch to at > - all. The choice of section is implied by the directive that we use > - to declare the object. */ > -#define SECTION_NOSWITCH 0x400000 > +enum section_flag > +{ > + /* This SECTION_STYLE is used for unnamed sections that we can switch > + to using a special assembler directive. */ > + SECTION_UNNAMED = 0, > + > + SECTION_ENTSIZE = (1UL << 8) - 1, /* entity size in section */ > + SECTION_CODE = 1UL << 8, /* contains code */ > + SECTION_WRITE = 1UL << 9, /* data is writable */ > + > + SECTION_DEBUG = 1UL << 10, /* contains debug data */ > + SECTION_LINKONCE = 1UL << 11, /* is linkonce */ > + SECTION_SMALL = 1UL << 12, /* contains "small data" */ > + SECTION_BSS = 1UL << 13, /* contains zeros only */ > + SECTION_MERGE = 1UL << 14, /* contains mergeable data */ > + SECTION_STRINGS = 1UL << 15, /* contains zero terminated strings > + without embedded zeros */ > + SECTION_OVERRIDE = 1UL << 16, /* allow override of default flags */ > + SECTION_TLS = 1UL << 17, /* contains thread-local storage */ > + SECTION_NOTYPE = 1UL << 18, /* don't output @progbits */ > + SECTION_DECLARED = 1UL << 19, /* section has been used */ > + > + /* This SECTION_STYLE is used for named sections that we can switch > + to using a general section directive. */ > + SECTION_NAMED = 1UL << 20, > + > + /* This SECTION_STYLE is used for sections that we cannot switch to at > + all. The choice of section is implied by the directive that we use > + to declare the object. */ > + SECTION_NOSWITCH = 1UL << 21, > + > + /* bits used for SECTION_STYLE */ > + SECTION_STYLE_MASK = SECTION_NAMED | SECTION_NOSWITCH, > + > + SECTION_COMMON = 1UL << 22, /* contains common data */ > + SECTION_RELRO = 1UL << 23, /* data is readonly after > + relocation processing */ > + SECTION_EXCLUDE = 1UL << 24, /* discarded by the linker */ > + SECTION_RETAIN = 1UL << 25, /* retained by the linker. */ > + SECTION_LINK_ORDER = 1UL << 26, /* section needs link-order. */ > + > + /* NB: The maximum SECTION_MACH_DEP is (1UL << 28) since AVR needs 4 bits > + in SECTION_MACH_DEP. */ > + SECTION_MACH_DEP = 1UL << 27, > + > + /* subsequent bits reserved for target */ > +}; > > /* A helper function for default_elf_select_section and > default_elf_unique_section. Categorizes the DECL. */ > diff --git a/gcc/varasm.c b/gcc/varasm.c > index 53cf6dea3f3..0a5f2e35bb0 100644 > --- a/gcc/varasm.c > +++ b/gcc/varasm.c > @@ -7821,10 +7821,7 @@ switch_to_section (section *new_section, tree decl) > else if (in_section == new_section) > return; > > - if (new_section->common.flags & SECTION_FORGET) > - in_section = NULL; > - else > - in_section = new_section; > + in_section = new_section; > > switch (SECTION_STYLE (new_section)) > {
On 9/7/2021 3:43 AM, Martin Liška wrote: > Hi. > > I'm planning some refactoring related to 'section *' and I noticed we > have > quite ugly mask definitions (of form 1UL << N), where SECTION_FORGET > is unused > and > > #define SECTION_STYLE_MASK 0x600000 /* bits used for SECTION_STYLE */ > > Is actually OR of 2 other values. What about making that a standard > enum value > with 1UL << N values? > > Patch can bootstrap on x86_64-linux-gnu and survives regression tests. > > Ready to be installed? > Thanks, > Martin > > gcc/ChangeLog: > > * output.h (enum section_flag): New. > (SECTION_FORGET): Remove. > (SECTION_ENTSIZE): Make it (1UL << 8) - 1. > (SECTION_STYLE_MASK): Define it based on other enum > values. > * varasm.c (switch_to_section): Remove unused handling of > SECTION_FORGET. OK jeff
diff --git a/gcc/output.h b/gcc/output.h index 73ca4545f4f..8f6f15308f4 100644 --- a/gcc/output.h +++ b/gcc/output.h @@ -365,44 +365,53 @@ extern void default_function_switched_text_sections (FILE *, tree, bool); extern void no_asm_to_stream (FILE *); /* Flags controlling properties of a section. */ -#define SECTION_ENTSIZE 0x000ff /* entity size in section */ -#define SECTION_CODE 0x00100 /* contains code */ -#define SECTION_WRITE 0x00200 /* data is writable */ -#define SECTION_DEBUG 0x00400 /* contains debug data */ -#define SECTION_LINKONCE 0x00800 /* is linkonce */ -#define SECTION_SMALL 0x01000 /* contains "small data" */ -#define SECTION_BSS 0x02000 /* contains zeros only */ -#define SECTION_FORGET 0x04000 /* forget that we've entered the section */ -#define SECTION_MERGE 0x08000 /* contains mergeable data */ -#define SECTION_STRINGS 0x10000 /* contains zero terminated strings without - embedded zeros */ -#define SECTION_OVERRIDE 0x20000 /* allow override of default flags */ -#define SECTION_TLS 0x40000 /* contains thread-local storage */ -#define SECTION_NOTYPE 0x80000 /* don't output @progbits */ -#define SECTION_DECLARED 0x100000 /* section has been used */ -#define SECTION_STYLE_MASK 0x600000 /* bits used for SECTION_STYLE */ -#define SECTION_COMMON 0x800000 /* contains common data */ -#define SECTION_RELRO 0x1000000 /* data is readonly after relocation processing */ -#define SECTION_EXCLUDE 0x2000000 /* discarded by the linker */ -#define SECTION_RETAIN 0x4000000 /* retained by the linker. */ -#define SECTION_LINK_ORDER 0x8000000 /* section needs link-order. */ - -/* NB: The maximum SECTION_MACH_DEP is 0x10000000 since AVR needs 4 bits - in SECTION_MACH_DEP. */ -#define SECTION_MACH_DEP 0x10000000 /* subsequent bits reserved for target */ - -/* This SECTION_STYLE is used for unnamed sections that we can switch - to using a special assembler directive. */ -#define SECTION_UNNAMED 0x000000 - -/* This SECTION_STYLE is used for named sections that we can switch - to using a general section directive. */ -#define SECTION_NAMED 0x200000 - -/* This SECTION_STYLE is used for sections that we cannot switch to at - all. The choice of section is implied by the directive that we use - to declare the object. */ -#define SECTION_NOSWITCH 0x400000 +enum section_flag +{ + /* This SECTION_STYLE is used for unnamed sections that we can switch + to using a special assembler directive. */ + SECTION_UNNAMED = 0, + + SECTION_ENTSIZE = (1UL << 8) - 1, /* entity size in section */ + SECTION_CODE = 1UL << 8, /* contains code */ + SECTION_WRITE = 1UL << 9, /* data is writable */ + + SECTION_DEBUG = 1UL << 10, /* contains debug data */ + SECTION_LINKONCE = 1UL << 11, /* is linkonce */ + SECTION_SMALL = 1UL << 12, /* contains "small data" */ + SECTION_BSS = 1UL << 13, /* contains zeros only */ + SECTION_MERGE = 1UL << 14, /* contains mergeable data */ + SECTION_STRINGS = 1UL << 15, /* contains zero terminated strings + without embedded zeros */ + SECTION_OVERRIDE = 1UL << 16, /* allow override of default flags */ + SECTION_TLS = 1UL << 17, /* contains thread-local storage */ + SECTION_NOTYPE = 1UL << 18, /* don't output @progbits */ + SECTION_DECLARED = 1UL << 19, /* section has been used */ + + /* This SECTION_STYLE is used for named sections that we can switch + to using a general section directive. */ + SECTION_NAMED = 1UL << 20, + + /* This SECTION_STYLE is used for sections that we cannot switch to at + all. The choice of section is implied by the directive that we use + to declare the object. */ + SECTION_NOSWITCH = 1UL << 21, + + /* bits used for SECTION_STYLE */ + SECTION_STYLE_MASK = SECTION_NAMED | SECTION_NOSWITCH, + + SECTION_COMMON = 1UL << 22, /* contains common data */ + SECTION_RELRO = 1UL << 23, /* data is readonly after + relocation processing */ + SECTION_EXCLUDE = 1UL << 24, /* discarded by the linker */ + SECTION_RETAIN = 1UL << 25, /* retained by the linker. */ + SECTION_LINK_ORDER = 1UL << 26, /* section needs link-order. */ + + /* NB: The maximum SECTION_MACH_DEP is (1UL << 28) since AVR needs 4 bits + in SECTION_MACH_DEP. */ + SECTION_MACH_DEP = 1UL << 27, + + /* subsequent bits reserved for target */ +}; /* A helper function for default_elf_select_section and default_elf_unique_section. Categorizes the DECL. */ diff --git a/gcc/varasm.c b/gcc/varasm.c index 53cf6dea3f3..0a5f2e35bb0 100644 --- a/gcc/varasm.c +++ b/gcc/varasm.c @@ -7821,10 +7821,7 @@ switch_to_section (section *new_section, tree decl) else if (in_section == new_section) return; - if (new_section->common.flags & SECTION_FORGET) - in_section = NULL; - else - in_section = new_section; + in_section = new_section; switch (SECTION_STYLE (new_section)) {