llvm-project/lld/ELF/Options.td

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include "llvm/Option/OptParser.td"
// For options whose names are multiple letters, either one dash or
// two can precede the option name except those that start with 'o'.
class F<string name>: Flag<["--", "-"], name>;
class J<string name>: Joined<["--", "-"], name>;
multiclass Eq<string name, string help> {
def NAME: Separate<["--", "-"], name>;
def NAME # _eq: Joined<["--", "-"], name # "=">, Alias<!cast<Separate>(NAME)>,
HelpText<help>;
}
multiclass B<string name, string help1, string help2> {
def NAME: Flag<["--", "-"], name>, HelpText<help1>;
def no_ # NAME: Flag<["--", "-"], "no-" # name>, HelpText<help2>;
}
defm auxiliary: Eq<"auxiliary", "Set DT_AUXILIARY field to the specified name">;
def Bsymbolic: F<"Bsymbolic">, HelpText<"Bind defined symbols locally">;
def Bsymbolic_functions: F<"Bsymbolic-functions">,
HelpText<"Bind defined function symbols locally">;
def Bdynamic: F<"Bdynamic">, HelpText<"Link against shared libraries (default)">;
def Bstatic: F<"Bstatic">, HelpText<"Do not link against shared libraries">;
def build_id: F<"build-id">, HelpText<"Alias for --build-id=fast">;
def build_id_eq: J<"build-id=">, HelpText<"Generate build ID note">,
MetaVarName<"[fast,md5,sha1,uuid,0x<hexstring>]">;
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defm check_sections: B<"check-sections",
"Check section addresses for overlaps (default)",
"Do not check section addresses for overlaps">;
defm compress_debug_sections:
Eq<"compress-debug-sections", "Compress DWARF debug sections">,
MetaVarName<"[none,zlib]">;
defm defsym: Eq<"defsym", "Define a symbol alias">, MetaVarName<"<symbol>=<value>">;
defm split_stack_adjust_size
: Eq<"split-stack-adjust-size",
"Specify adjustment to stack size when a split-stack function calls a "
"non-split-stack function">,
MetaVarName<"<value>">;
defm library_path:
Eq<"library-path", "Add a directory to the library search path">, MetaVarName<"<dir>">;
def O: JoinedOrSeparate<["-"], "O">, HelpText<"Optimize output file size">;
defm Tbss: Eq<"Tbss", "Same as --section-start with .bss as the sectionname">;
defm Tdata: Eq<"Tdata", "Same as --section-start with .data as the sectionname">;
defm Ttext: Eq<"Ttext", "Same as --section-start with .text as the sectionname">;
defm allow_multiple_definition: B<"allow-multiple-definition",
"Allow multiple definitions",
"Do not allow multiple definitions (default)">;
defm allow_shlib_undefined: B<"allow-shlib-undefined",
"Allow unresolved references in shared libraries (default when linking a shared library)",
"Do not allow unresolved references in shared libraries (default when linking an executable)">;
defm apply_dynamic_relocs: B<"apply-dynamic-relocs",
"Apply link-time values for dynamic relocations",
"Do not apply link-time values for dynamic relocations (default)">;
defm as_needed: B<"as-needed",
"Only set DT_NEEDED for shared libraries if used",
"Always set DT_NEEDED for shared libraries (default)">;
defm call_graph_ordering_file:
Eq<"call-graph-ordering-file", "Layout sections to optimize the given callgraph">;
defm call_graph_profile_sort: B<"call-graph-profile-sort",
"Reorder sections with call graph profile (default)",
"Do not reorder sections with call graph profile">;
// -chroot doesn't have a help text because it is an internal option.
def chroot: Separate<["--", "-"], "chroot">;
def color_diagnostics: F<"color-diagnostics">,
HelpText<"Alias for --color-diagnostics=always">;
def color_diagnostics_eq: J<"color-diagnostics=">,
HelpText<"Use colors in diagnostics">,
MetaVarName<"[auto,always,never]">;
defm cref: B<"cref",
"Output cross reference table",
"Do not output cross reference table">;
defm define_common: B<"define-common",
"Assign space to common symbols",
"Do not assign space to common symbols">;
defm demangle: B<"demangle",
"Demangle symbol names (default)",
"Do not demangle symbol names">;
def disable_new_dtags: F<"disable-new-dtags">,
HelpText<"Disable new dynamic tags">;
def discard_all: F<"discard-all">, HelpText<"Delete all local symbols">;
def discard_locals: F<"discard-locals">,
HelpText<"Delete temporary local symbols">;
def discard_none: F<"discard-none">,
HelpText<"Keep all symbols in the symbol table">;
defm dynamic_linker: Eq<"dynamic-linker", "Which dynamic linker to use">;
defm dynamic_list: Eq<"dynamic-list", "Read a list of dynamic symbols">;
defm eh_frame_hdr: B<"eh-frame-hdr",
"Request creation of .eh_frame_hdr section and PT_GNU_EH_FRAME segment header",
"Do not create .eh_frame_hdr section">;
def emit_relocs: F<"emit-relocs">, HelpText<"Generate relocations in output">;
def enable_new_dtags: F<"enable-new-dtags">,
HelpText<"Enable new dynamic tags (default)">;
Add --warn-backrefs to maintain compatibility with other linkers I'm proposing a new command line flag, --warn-backrefs in this patch. The flag and the feature proposed below don't exist in GNU linkers nor the current lld. --warn-backrefs is an option to detect reverse or cyclic dependencies between static archives, and it can be used to keep your program compatible with GNU linkers after you switch to lld. I'll explain the feature and why you may find it useful below. lld's symbol resolution semantics is more relaxed than traditional Unix linkers. Therefore, ld.lld foo.a bar.o succeeds even if bar.o contains an undefined symbol that have to be resolved by some object file in foo.a. Traditional Unix linkers don't allow this kind of backward reference, as they visit each file only once from left to right in the command line while resolving all undefined symbol at the moment of visiting. In the above case, since there's no undefined symbol when a linker visits foo.a, no files are pulled out from foo.a, and because the linker forgets about foo.a after visiting, it can't resolve undefined symbols that could have been resolved otherwise. That lld accepts more relaxed form means (besides it makes more sense) that you can accidentally write a command line or a build file that works only with lld, even if you have a plan to distribute it to wider users who may be using GNU linkers. With --check-library-dependency, you can detect a library order that doesn't work with other Unix linkers. The option is also useful to detect cyclic dependencies between static archives. Again, lld accepts ld.lld foo.a bar.a even if foo.a and bar.a depend on each other. With --warn-backrefs it is handled as an error. Here is how the option works. We assign a group ID to each file. A file with a smaller group ID can pull out object files from an archive file with an equal or greater group ID. Otherwise, it is a reverse dependency and an error. A file outside --{start,end}-group gets a fresh ID when instantiated. All files within the same --{start,end}-group get the same group ID. E.g. ld.lld A B --start-group C D --end-group E A and B form group 0, C, D and their member object files form group 1, and E forms group 2. I think that you can see how this group assignment rule simulates the traditional linker's semantics. Differential Revision: https://reviews.llvm.org/D45195 llvm-svn: 329636
2018-04-10 07:05:48 +08:00
def end_group: F<"end-group">,
HelpText<"Ignored for compatibility with GNU unless you pass --warn-backrefs">;
def end_lib: F<"end-lib">,
HelpText<"End a grouping of objects that should be treated as if they were together in an archive">;
defm entry: Eq<"entry", "Name of entry point symbol">,
MetaVarName<"<entry>">;
defm error_limit:
Eq<"error-limit", "Maximum number of errors to emit before stopping (0 = no limit)">;
def error_unresolved_symbols: F<"error-unresolved-symbols">,
HelpText<"Report unresolved symbols as errors">;
defm exclude_libs: Eq<"exclude-libs", "Exclude static libraries from automatic export">;
defm execute_only: B<"execute-only",
"Mark executable sections unreadable",
"Mark executable sections readable (default)">;
defm export_dynamic: B<"export-dynamic",
"Put symbols in the dynamic symbol table",
"Do not put symbols in the dynamic symbol table (default)">;
defm export_dynamic_symbol:
Eq<"export-dynamic-symbol", "Put a symbol in the dynamic symbol table">;
defm fatal_warnings: B<"fatal-warnings",
"Treat warnings as errors",
"Do not treat warnings as errors (default)">;
defm filter: Eq<"filter", "Set DT_FILTER field to the specified name">;
defm fini: Eq<"fini", "Specify a finalizer function">, MetaVarName<"<symbol>">;
def fix_cortex_a53_843419: F<"fix-cortex-a53-843419">,
HelpText<"Apply fixes for AArch64 Cortex-A53 erratum 843419">;
defm format: Eq<"format", "Change the input format of the inputs following this option">,
MetaVarName<"[default,elf,binary]">;
defm gc_sections: B<"gc-sections",
"Enable garbage collection of unused sections",
"Disable garbage collection of unused sections (default)">;
defm gdb_index: B<"gdb-index",
"Generate .gdb_index section",
"Do not generate .gdb_index section (default)">;
defm gnu_unique: B<"gnu-unique",
"Enable STB_GNU_UNIQUE symbol binding (default)",
"Disable STB_GNU_UNIQUE symbol binding">;
defm hash_style: Eq<"hash-style", "Specify hash style (sysv, gnu or both)">;
def help: F<"help">, HelpText<"Print option help">;
def icf_all: F<"icf=all">, HelpText<"Enable identical code folding">;
def icf_safe: F<"icf=safe">, HelpText<"Enable safe identical code folding">;
def icf_none: F<"icf=none">, HelpText<"Disable identical code folding (default)">;
def ignore_function_address_equality: F<"ignore-function-address-equality">,
HelpText<"lld can break the address equality of functions">;
def ignore_data_address_equality: F<"ignore-data-address-equality">,
HelpText<"lld can break the address equality of data">;
defm image_base: Eq<"image-base", "Set the base address">;
defm init: Eq<"init", "Specify an initializer function">,
MetaVarName<"<symbol>">;
defm just_symbols: Eq<"just-symbols", "Just link symbols">;
defm keep_unique: Eq<"keep-unique", "Do not fold this symbol during ICF">;
defm library: Eq<"library", "Root name of library to use">,
MetaVarName<"<libName>">;
def m: JoinedOrSeparate<["-"], "m">, HelpText<"Set target emulation">;
defm Map: Eq<"Map", "Print a link map to the specified file">;
defm merge_exidx_entries: B<"merge-exidx-entries",
"Enable merging .ARM.exidx entries (default)",
"Disable merging .ARM.exidx entries">;
def nmagic: F<"nmagic">, MetaVarName<"<magic>">,
HelpText<"Do not page align sections, link against static libraries.">;
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def nostdlib: F<"nostdlib">,
HelpText<"Only search directories specified on the command line">;
def no_color_diagnostics: F<"no-color-diagnostics">,
HelpText<"Do not use colors in diagnostics">;
def no_dynamic_linker: F<"no-dynamic-linker">,
HelpText<"Inhibit output of .interp section">;
def noinhibit_exec: F<"noinhibit-exec">,
HelpText<"Retain the executable output file whenever it is still usable">;
def no_nmagic: F<"no-nmagic">, MetaVarName<"<magic>">,
HelpText<"Page align sections (default)">;
def no_omagic: F<"no-omagic">, MetaVarName<"<magic>">,
HelpText<"Do not set the text data sections to be writable, page align sections (default)">;
def no_rosegment: F<"no-rosegment">,
HelpText<"Do not put read-only non-executable sections in their own segment">;
def no_undefined: F<"no-undefined">,
HelpText<"Report unresolved symbols even if the linker is creating a shared library">;
def o: JoinedOrSeparate<["-"], "o">, MetaVarName<"<path>">,
HelpText<"Path to file to write output">;
def oformat: Separate<["--"], "oformat">, MetaVarName<"<format>">,
HelpText<"Specify the binary format for the output object file">;
def omagic: Flag<["--"], "omagic">, MetaVarName<"<magic>">,
HelpText<"Set the text and data sections to be readable and writable, do not page align sections, link against static libraries">;
defm orphan_handling:
Eq<"orphan-handling", "Control how orphan sections are handled when linker script used">;
defm pack_dyn_relocs:
Eq<"pack-dyn-relocs", "Pack dynamic relocations in the given format">,
MetaVarName<"[none,android,relr,android+relr]">;
defm use_android_relr_tags: B<"use-android-relr-tags",
"Use SHT_ANDROID_RELR / DT_ANDROID_RELR* tags instead of SHT_RELR / DT_RELR*",
"Use SHT_RELR / DT_RELR* tags (default)">;
def pic_veneer: F<"pic-veneer">,
HelpText<"Always generate position independent thunks (veneers)">;
defm pie: B<"pie",
"Create a position independent executable",
"Do not create a position independent executable (default)">;
defm print_gc_sections: B<"print-gc-sections",
"List removed unused sections",
"Do not list removed unused sections (default)">;
defm print_icf_sections: B<"print-icf-sections",
"List identical folded sections",
"Do not list identical folded sections (default)">;
defm print_symbol_order: Eq<"print-symbol-order",
"Print a symbol order specified by --call-graph-ordering-file into the speficied file">;
def pop_state: F<"pop-state">,
HelpText<"Undo the effect of -push-state">;
def push_state: F<"push-state">,
HelpText<"Save the current state of -as-needed, -static and -whole-archive">;
def print_map: F<"print-map">,
HelpText<"Print a link map to the standard output">;
defm reproduce: Eq<"reproduce", "Dump linker invocation and input files for debugging">;
defm rpath: Eq<"rpath", "Add a DT_RUNPATH to the output">;
def relocatable: F<"relocatable">, HelpText<"Create relocatable object file">;
defm retain_symbols_file:
Eq<"retain-symbols-file", "Retain only the symbols listed in the file">,
MetaVarName<"<file>">;
defm script: Eq<"script", "Read linker script">;
defm section_start: Eq<"section-start", "Set address of section">,
MetaVarName<"<address>">;
def shared: F<"shared">, HelpText<"Build a shared object">;
defm soname: Eq<"soname", "Set DT_SONAME">;
defm sort_section:
Eq<"sort-section", "Specifies sections sorting rule when linkerscript is used">;
Add --warn-backrefs to maintain compatibility with other linkers I'm proposing a new command line flag, --warn-backrefs in this patch. The flag and the feature proposed below don't exist in GNU linkers nor the current lld. --warn-backrefs is an option to detect reverse or cyclic dependencies between static archives, and it can be used to keep your program compatible with GNU linkers after you switch to lld. I'll explain the feature and why you may find it useful below. lld's symbol resolution semantics is more relaxed than traditional Unix linkers. Therefore, ld.lld foo.a bar.o succeeds even if bar.o contains an undefined symbol that have to be resolved by some object file in foo.a. Traditional Unix linkers don't allow this kind of backward reference, as they visit each file only once from left to right in the command line while resolving all undefined symbol at the moment of visiting. In the above case, since there's no undefined symbol when a linker visits foo.a, no files are pulled out from foo.a, and because the linker forgets about foo.a after visiting, it can't resolve undefined symbols that could have been resolved otherwise. That lld accepts more relaxed form means (besides it makes more sense) that you can accidentally write a command line or a build file that works only with lld, even if you have a plan to distribute it to wider users who may be using GNU linkers. With --check-library-dependency, you can detect a library order that doesn't work with other Unix linkers. The option is also useful to detect cyclic dependencies between static archives. Again, lld accepts ld.lld foo.a bar.a even if foo.a and bar.a depend on each other. With --warn-backrefs it is handled as an error. Here is how the option works. We assign a group ID to each file. A file with a smaller group ID can pull out object files from an archive file with an equal or greater group ID. Otherwise, it is a reverse dependency and an error. A file outside --{start,end}-group gets a fresh ID when instantiated. All files within the same --{start,end}-group get the same group ID. E.g. ld.lld A B --start-group C D --end-group E A and B form group 0, C, D and their member object files form group 1, and E forms group 2. I think that you can see how this group assignment rule simulates the traditional linker's semantics. Differential Revision: https://reviews.llvm.org/D45195 llvm-svn: 329636
2018-04-10 07:05:48 +08:00
def start_group: F<"start-group">,
HelpText<"Ignored for compatibility with GNU unless you pass --warn-backrefs">;
def start_lib: F<"start-lib">,
HelpText<"Start a grouping of objects that should be treated as if they were together in an archive">;
def strip_all: F<"strip-all">, HelpText<"Strip all symbols">;
def strip_debug: F<"strip-debug">, HelpText<"Strip debugging information">;
defm symbol_ordering_file:
Eq<"symbol-ordering-file", "Layout sections to place symbols in the order specified by symbol ordering file">;
defm sysroot: Eq<"sysroot", "Set the system root">;
def target1_rel: F<"target1-rel">, HelpText<"Interpret R_ARM_TARGET1 as R_ARM_REL32">;
def target1_abs: F<"target1-abs">, HelpText<"Interpret R_ARM_TARGET1 as R_ARM_ABS32 (default)">;
defm target2:
Eq<"target2", "Interpret R_ARM_TARGET2 as <type>, where <type> is one of rel, abs, or got-rel">,
MetaVarName<"<type>">;
defm threads: B<"threads",
"Run the linker multi-threaded (default)",
"Do not run the linker multi-threaded">;
defm toc_optimize : B<"toc-optimize",
"(PowerPC64) Enable TOC related optimizations (default)",
"(PowerPC64) Disable TOC related optimizations">;
def trace: F<"trace">, HelpText<"Print the names of the input files">;
defm trace_symbol: Eq<"trace-symbol", "Trace references to symbols">;
defm undefined: Eq<"undefined", "Force undefined symbol during linking">,
MetaVarName<"<symbol>">;
defm unresolved_symbols:
Eq<"unresolved-symbols", "Determine how to handle unresolved symbols">;
defm undefined_version: B<"undefined-version",
"Allow unused version in version script (default)",
"Report version scripts that refer undefined symbols">;
defm rsp_quoting: Eq<"rsp-quoting", "Quoting style for response files">,
MetaVarName<"[posix,windows]">;
def v: Flag<["-"], "v">, HelpText<"Display the version number">;
def verbose: F<"verbose">, HelpText<"Verbose mode">;
def version: F<"version">, HelpText<"Display the version number and exit">;
defm version_script: Eq<"version-script", "Read a version script">;
Add --warn-backrefs to maintain compatibility with other linkers I'm proposing a new command line flag, --warn-backrefs in this patch. The flag and the feature proposed below don't exist in GNU linkers nor the current lld. --warn-backrefs is an option to detect reverse or cyclic dependencies between static archives, and it can be used to keep your program compatible with GNU linkers after you switch to lld. I'll explain the feature and why you may find it useful below. lld's symbol resolution semantics is more relaxed than traditional Unix linkers. Therefore, ld.lld foo.a bar.o succeeds even if bar.o contains an undefined symbol that have to be resolved by some object file in foo.a. Traditional Unix linkers don't allow this kind of backward reference, as they visit each file only once from left to right in the command line while resolving all undefined symbol at the moment of visiting. In the above case, since there's no undefined symbol when a linker visits foo.a, no files are pulled out from foo.a, and because the linker forgets about foo.a after visiting, it can't resolve undefined symbols that could have been resolved otherwise. That lld accepts more relaxed form means (besides it makes more sense) that you can accidentally write a command line or a build file that works only with lld, even if you have a plan to distribute it to wider users who may be using GNU linkers. With --check-library-dependency, you can detect a library order that doesn't work with other Unix linkers. The option is also useful to detect cyclic dependencies between static archives. Again, lld accepts ld.lld foo.a bar.a even if foo.a and bar.a depend on each other. With --warn-backrefs it is handled as an error. Here is how the option works. We assign a group ID to each file. A file with a smaller group ID can pull out object files from an archive file with an equal or greater group ID. Otherwise, it is a reverse dependency and an error. A file outside --{start,end}-group gets a fresh ID when instantiated. All files within the same --{start,end}-group get the same group ID. E.g. ld.lld A B --start-group C D --end-group E A and B form group 0, C, D and their member object files form group 1, and E forms group 2. I think that you can see how this group assignment rule simulates the traditional linker's semantics. Differential Revision: https://reviews.llvm.org/D45195 llvm-svn: 329636
2018-04-10 07:05:48 +08:00
defm warn_backrefs: B<"warn-backrefs",
"Warn about backward symbol references to fetch archive members",
"Do not warn about backward symbol references to fetch archive members (default)">;
Add --warn-backrefs to maintain compatibility with other linkers I'm proposing a new command line flag, --warn-backrefs in this patch. The flag and the feature proposed below don't exist in GNU linkers nor the current lld. --warn-backrefs is an option to detect reverse or cyclic dependencies between static archives, and it can be used to keep your program compatible with GNU linkers after you switch to lld. I'll explain the feature and why you may find it useful below. lld's symbol resolution semantics is more relaxed than traditional Unix linkers. Therefore, ld.lld foo.a bar.o succeeds even if bar.o contains an undefined symbol that have to be resolved by some object file in foo.a. Traditional Unix linkers don't allow this kind of backward reference, as they visit each file only once from left to right in the command line while resolving all undefined symbol at the moment of visiting. In the above case, since there's no undefined symbol when a linker visits foo.a, no files are pulled out from foo.a, and because the linker forgets about foo.a after visiting, it can't resolve undefined symbols that could have been resolved otherwise. That lld accepts more relaxed form means (besides it makes more sense) that you can accidentally write a command line or a build file that works only with lld, even if you have a plan to distribute it to wider users who may be using GNU linkers. With --check-library-dependency, you can detect a library order that doesn't work with other Unix linkers. The option is also useful to detect cyclic dependencies between static archives. Again, lld accepts ld.lld foo.a bar.a even if foo.a and bar.a depend on each other. With --warn-backrefs it is handled as an error. Here is how the option works. We assign a group ID to each file. A file with a smaller group ID can pull out object files from an archive file with an equal or greater group ID. Otherwise, it is a reverse dependency and an error. A file outside --{start,end}-group gets a fresh ID when instantiated. All files within the same --{start,end}-group get the same group ID. E.g. ld.lld A B --start-group C D --end-group E A and B form group 0, C, D and their member object files form group 1, and E forms group 2. I think that you can see how this group assignment rule simulates the traditional linker's semantics. Differential Revision: https://reviews.llvm.org/D45195 llvm-svn: 329636
2018-04-10 07:05:48 +08:00
defm warn_common: B<"warn-common",
"Warn about duplicate common symbols",
"Do not warn about duplicate common symbols (default)">;
defm warn_ifunc_textrel: B<"warn-ifunc-textrel",
"Warn about using ifunc symbols with text relocations",
"Do not warn about using ifunc symbols with text relocations (default)">;
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defm warn_symbol_ordering: B<"warn-symbol-ordering",
"Warn about problems with the symbol ordering file (default)",
"Do not warn about problems with the symbol ordering file">;
def warn_unresolved_symbols: F<"warn-unresolved-symbols">,
HelpText<"Report unresolved symbols as warnings">;
defm whole_archive: B<"whole-archive",
"Force load of all members in a static library",
"Do not force load of all members in a static library (default)">;
defm wrap: Eq<"wrap", "Use wrapper functions for symbol">,
MetaVarName<"<symbol>=<symbol>">;
def z: JoinedOrSeparate<["-"], "z">, MetaVarName<"<option>">,
HelpText<"Linker option extensions">;
// Aliases
def: Separate<["-"], "f">, Alias<auxiliary>, HelpText<"Alias for --auxiliary">;
def: F<"call_shared">, Alias<Bdynamic>, HelpText<"Alias for --Bdynamic">;
def: F<"dy">, Alias<Bdynamic>, HelpText<"Alias for --Bdynamic">;
def: F<"dn">, Alias<Bstatic>, HelpText<"Alias for --Bstatic">;
def: F<"non_shared">, Alias<Bstatic>, HelpText<"Alias for --Bstatic">;
def: F<"static">, Alias<Bstatic>, HelpText<"Alias for --Bstatic">;
def: Flag<["-"], "d">, Alias<define_common>, HelpText<"Alias for --define-common">;
def: F<"dc">, Alias<define_common>, HelpText<"Alias for --define-common">;
def: F<"dp">, Alias<define_common>, HelpText<"Alias for --define-common">;
def: Flag<["-"], "x">, Alias<discard_all>, HelpText<"Alias for --discard-all">;
def: Flag<["-"], "X">, Alias<discard_locals>, HelpText<"Alias for --discard-locals">;
def: Flag<["-"], "q">, Alias<emit_relocs>, HelpText<"Alias for --emit-relocs">;
def: Flag<["-"], ")">, Alias<end_group>, HelpText<"Alias for --end-group">;
def: JoinedOrSeparate<["-"], "e">, Alias<entry>, HelpText<"Alias for --entry">;
def: Flag<["-"], "E">, Alias<export_dynamic>, HelpText<"Alias for --export-dynamic">;
def: Separate<["-"], "F">, Alias<filter>, HelpText<"Alias for --filter">;
def: Separate<["-"], "b">, Alias<format>, HelpText<"Alias for --format">;
def: JoinedOrSeparate<["-"], "l">, Alias<library>, HelpText<"Alias for --library">;
def: JoinedOrSeparate<["-"], "L">, Alias<library_path>, HelpText<"Alias for --library-path">;
def: F<"no-pic-executable">, Alias<no_pie>, HelpText<"Alias for --no-pie">;
def: Flag<["-"], "n">, Alias<nmagic>, HelpText<"Alias for --nmagic">;
def: Flag<["-"], "N">, Alias<omagic>, HelpText<"Alias for --omagic">;
def: Joined<["--"], "output=">, Alias<o>, HelpText<"Alias for -o">;
def: Separate<["--"], "output">, Alias<o>, HelpText<"Alias for -o">;
def: F<"pic-executable">, Alias<pie>, HelpText<"Alias for --pie">;
def: Flag<["-"], "M">, Alias<print_map>, HelpText<"Alias for --print-map">;
def: Flag<["-"], "r">, Alias<relocatable>, HelpText<"Alias for --relocatable">;
def: JoinedOrSeparate<["-"], "R">, Alias<rpath>, HelpText<"Alias for --rpath">;
def: JoinedOrSeparate<["-"], "T">, Alias<script>, HelpText<"Alias for --script">;
def: F<"Bshareable">, Alias<shared>, HelpText<"Alias for --shared">;
def: JoinedOrSeparate<["-"], "h">, Alias<soname>, HelpText<"Alias for --soname">;
def: Flag<["-"], "(">, Alias<start_group>, HelpText<"Alias for --start-group">;
def: Flag<["-"], "s">, Alias<strip_all>, HelpText<"Alias for --strip-all">;
def: Flag<["-"], "S">, Alias<strip_debug>, HelpText<"Alias for --strip-debug">;
def: Flag<["-"], "t">, Alias<trace>, HelpText<"Alias for --trace">;
def: JoinedOrSeparate<["-"], "y">, Alias<trace_symbol>, HelpText<"Alias for --trace-symbol">;
def: Separate<["-", "--"], "Ttext-segment">, Alias<Ttext>, HelpText<"Alias for --Ttext">;
def: Joined<["-", "--"], "Ttext-segment=">, Alias<Ttext>, HelpText<"Alias for --Ttext">;
def: JoinedOrSeparate<["-"], "u">, Alias<undefined>, HelpText<"Alias for --undefined">;
def: Flag<["-"], "V">, Alias<version>, HelpText<"Alias for --version">;
// LTO-related options.
def lto_aa_pipeline: J<"lto-aa-pipeline=">,
HelpText<"AA pipeline to run during LTO. Used in conjunction with -lto-newpm-passes">;
def lto_debug_pass_manager: F<"lto-debug-pass-manager">,
HelpText<"Debug new pass manager">;
def lto_new_pass_manager: F<"lto-new-pass-manager">,
HelpText<"Use new pass manager">;
def lto_newpm_passes: J<"lto-newpm-passes=">,
HelpText<"Passes to run during LTO">;
def lto_O: J<"lto-O">, MetaVarName<"<opt-level>">,
HelpText<"Optimization level for LTO">;
def lto_partitions: J<"lto-partitions=">,
HelpText<"Number of LTO codegen partitions">;
def lto_cs_profile_generate: F<"lto-cs-profile-generate">,
HelpText<"Perform context senstive PGO instrumentation">;
def lto_cs_profile_file: J<"lto-cs-profile-file=">,
HelpText<"Context sensitive profile file path">;
def lto_sample_profile: J<"lto-sample-profile=">,
HelpText<"Sample profile file path">;
def disable_verify: F<"disable-verify">;
defm mllvm: Eq<"mllvm", "Additional arguments to forward to LLVM's option processing">;
def opt_remarks_filename: Separate<["--"], "opt-remarks-filename">,
HelpText<"YAML output file for optimization remarks">;
def opt_remarks_passes: Separate<["--"], "opt-remarks-passes">,
HelpText<"Regex for the passes that need to be serialized to the output file">;
def opt_remarks_with_hotness: Flag<["--"], "opt-remarks-with-hotness">,
HelpText<"Include hotness information in the optimization remarks file">;
defm plugin_opt: Eq<"plugin-opt", "specifies LTO options for compatibility with GNU linkers">;
def save_temps: F<"save-temps">;
def thinlto_cache_dir: J<"thinlto-cache-dir=">,
HelpText<"Path to ThinLTO cached object file directory">;
defm thinlto_cache_policy: Eq<"thinlto-cache-policy", "Pruning policy for the ThinLTO cache">;
def thinlto_jobs: J<"thinlto-jobs=">, HelpText<"Number of ThinLTO jobs">;
def: J<"plugin-opt=O">, Alias<lto_O>, HelpText<"Alias for -lto-O">;
def: F<"plugin-opt=debug-pass-manager">,
Alias<lto_debug_pass_manager>, HelpText<"Alias for -lto-debug-pass-manager">;
def: F<"plugin-opt=disable-verify">, Alias<disable_verify>, HelpText<"Alias for -disable-verify">;
def plugin_opt_dwo_dir_eq: J<"plugin-opt=dwo_dir=">,
HelpText<"Directory to store .dwo files when LTO and debug fission are used">;
def plugin_opt_emit_llvm: F<"plugin-opt=emit-llvm">;
def: J<"plugin-opt=jobs=">, Alias<thinlto_jobs>, HelpText<"Alias for -thinlto-jobs">;
def: J<"plugin-opt=lto-partitions=">, Alias<lto_partitions>, HelpText<"Alias for -lto-partitions">;
def plugin_opt_mcpu_eq: J<"plugin-opt=mcpu=">;
def: F<"plugin-opt=new-pass-manager">,
Alias<lto_new_pass_manager>, HelpText<"Alias for -lto-new-pass-manager">;
def plugin_opt_obj_path_eq: J<"plugin-opt=obj-path=">;
def: F<"plugin-opt=cs-profile-generate">,
Alias<lto_cs_profile_generate>, HelpText<"Alias for -lto-cs-profile-generate">;
def: J<"plugin-opt=cs-profile-path=">,
Alias<lto_cs_profile_file>, HelpText<"Alias for -lto-cs-profile-file">;
def: J<"plugin-opt=sample-profile=">,
Alias<lto_sample_profile>, HelpText<"Alias for -lto-sample-profile">;
def: F<"plugin-opt=save-temps">, Alias<save_temps>, HelpText<"Alias for -save-temps">;
def plugin_opt_thinlto_emit_imports_files: F<"plugin-opt=thinlto-emit-imports-files">;
def plugin_opt_thinlto_index_only: F<"plugin-opt=thinlto-index-only">;
def plugin_opt_thinlto_index_only_eq: J<"plugin-opt=thinlto-index-only=">;
def plugin_opt_thinlto_object_suffix_replace_eq: J<"plugin-opt=thinlto-object-suffix-replace=">;
def plugin_opt_thinlto_prefix_replace_eq: J<"plugin-opt=thinlto-prefix-replace=">;
// Ignore LTO plugin-related options.
// clang -flto passes -plugin and -plugin-opt to the linker. This is required
// for ld.gold and ld.bfd to get LTO working. But it's not for lld which doesn't
// rely on a plugin. Instead of detecting which linker is used on clang side we
// just ignore the option on lld side as it's easier. In fact, the linker could
// be called 'ld' and understanding which linker is used would require parsing of
// --version output.
defm plugin: Eq<"plugin", "Ignored for compatibility with GNU linkers">;
def plugin_opt_fresolution_eq: J<"plugin-opt=-fresolution=">;
def plugin_opt_pass_through_eq: J<"plugin-opt=-pass-through=">;
def plugin_opt_thinlto: J<"plugin-opt=thinlto">;
def plugin_opt_slash: J<"plugin-opt=/">;
// Options listed below are silently ignored for now for compatibility.
def: F<"detect-odr-violations">;
def: Flag<["-"], "g">;
def: F<"long-plt">;
def: F<"no-add-needed">;
def: F<"no-copy-dt-needed-entries">;
def: F<"no-ctors-in-init-array">;
def: F<"no-keep-memory">;
def: F<"no-mmap-output-file">;
def: F<"no-pipeline-knowledge">;
def: F<"no-warn-mismatch">;
def: Flag<["-"], "p">;
def: Separate<["--", "-"], "rpath-link">;
def: J<"rpath-link=">;
def: F<"sort-common">;
def: F<"stats">;
def: F<"warn-execstack">;
def: F<"warn-once">;
def: F<"warn-shared-textrel">;
def: F<"EB">;
def: F<"EL">;
def: JoinedOrSeparate<["-"], "G">;
def: F<"Qy">;
[ELF][MIPS] Multi-GOT implementation Almost all entries inside MIPS GOT are referenced by signed 16-bit index. Zero entry lies approximately in the middle of the GOT. So the total number of GOT entries cannot exceed ~16384 for 32-bit architecture and ~8192 for 64-bit architecture. This limitation makes impossible to link rather large application like for example LLVM+Clang. There are two workaround for this problem. The first one is using the -mxgot compiler's flag. It enables using a 32-bit index to access GOT entries. But each access requires two assembly instructions two load GOT entry index to a register. Another workaround is multi-GOT. This patch implements it. Here is a brief description of multi-GOT for detailed one see the following link https://dmz-portal.mips.com/wiki/MIPS_Multi_GOT. If the sum of local, global and tls entries is less than 64K only single got is enough. Otherwise, multi-got is created. Series of primary and multiple secondary GOTs have the following layout: ``` - Primary GOT Header Local entries Global entries Relocation only entries TLS entries - Secondary GOT Local entries Global entries TLS entries ... ``` All GOT entries required by relocations from a single input file entirely belong to either primary or one of secondary GOTs. To reference GOT entries each GOT has its own _gp value points to the "middle" of the GOT. In the code this value loaded to the register which is used for GOT access. MIPS 32 function's prologue: ``` lui v0,0x0 0: R_MIPS_HI16 _gp_disp addiu v0,v0,0 4: R_MIPS_LO16 _gp_disp ``` MIPS 64 function's prologue: ``` lui at,0x0 14: R_MIPS_GPREL16 main ``` Dynamic linker does not know anything about secondary GOTs and cannot use a regular MIPS mechanism for GOT entries initialization. So we have to use an approach accepted by other architectures and create dynamic relocations R_MIPS_REL32 to initialize global entries (and local in case of PIC code) in secondary GOTs. But ironically MIPS dynamic linker requires GOT entries and correspondingly ordered dynamic symbol table entries to deal with dynamic relocations. To handle this problem relocation-only section in the primary GOT contains entries for all symbols referenced in global parts of secondary GOTs. Although the sum of local and normal global entries of the primary got should be less than 64K, the size of the primary got (including relocation-only entries can be greater than 64K, because parts of the primary got that overflow the 64K limit are used only by the dynamic linker at dynamic link-time and not by 16-bit gp-relative addressing at run-time. The patch affects common LLD code in the following places: - Added new hidden -mips-got-size flag. This flag required to set low maximum size of a single GOT to be able to test the implementation using small test cases. - Added InputFile argument to the getRelocTargetVA function. The same symbol referenced by GOT relocation from different input file might be allocated in different GOT. So result of relocation depends on the file. - Added new ctor to the DynamicReloc class. This constructor records settings of dynamic relocation which used to adjust address of 64kb page lies inside a specific output section. With the patch LLD is able to link all LLVM+Clang+LLD applications and libraries for MIPS 32/64 targets. Differential revision: https://reviews.llvm.org/D31528 llvm-svn: 334390
2018-06-11 15:24:31 +08:00
// Hidden option used for testing MIPS multi-GOT implementation.
defm mips_got_size:
Eq<"mips-got-size", "Max size of a single MIPS GOT. 0x10000 by default.">,
Flags<[HelpHidden]>;