[llvm-readobj] Make -s and -t match llvm-readelf

llvm-readobj is an internal testing tool for binary formats. Its output and
command line options do not need to be stable. It isn't supposed to be part of a
build process.

llvm-readelf was created as a user-facing utility and its interface intends to
be compatible with GNU readelf (unless there are good reasons not to).

The two tools have mostly compatible options. -s and -t are noticeable
exceptions due to history. I think the cost of keeping the inconsistency
overweighs the little history-compatible benefit and hinders transition from
cl::opt to OptTable, so let's change it.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D105055

Author: MaskRay

llvm/docs/CommandGuide/llvm-readobj.rst

@@ -95,7 +95,7 @@ file formats.
 
  Display the relocation entries in the file.
 
-.. option:: --sections, --section-headers, -s, -S
+.. option:: --sections, --section-headers, -S
 
  Display all sections.
 
@@ -123,7 +123,7 @@ file formats.
  Display the specified section(s) as a list of strings. ``section`` may be a
  section index or section name.
 
-.. option:: --symbols, --syms, -t
+.. option:: --symbols, --syms, -s
 
  Display the symbol table.
 

llvm/docs/ReleaseNotes.rst

@@ -164,6 +164,11 @@ Changes to the LLVM tools
   ``--x86-asm-syntax`` is a deprecated internal option which will be removed in LLVM 14.0.0.
   (`D101695 <https://reviews.llvm.org/D101695>`_)
 
+* The llvm-readobj short aliases ``-s`` (previously ``--sections``) and ``-t``
+  (previously ``--syms``) have been changed to ``--syms`` and
+  ``--section-details`` respectively, to match llvm-readelf.
+  (`D105055 <https://reviews.llvm.org/D105055>`_)
+
 Changes to LLDB
 ---------------------------------
 

llvm/test/tools/llvm-readobj/ELF/merged.test

@@ -52,7 +52,7 @@ DynamicSymbols:
 ## llvm-readobj does not support merged args, because it also supports some old
 ## flags (-st, -sd, etc.), and it would be confusing if only some merged args
 ## were supported.
-# RUN: not llvm-readobj -aeWhSrnudlVgIs %t.o 2>&1 | FileCheck %s --check-prefix=UNKNOWN
+# RUN: not llvm-readobj -aeWhSsrnudlVgIS %t.o 2>&1 | FileCheck %s --check-prefix=UNKNOWN
 
 # CHECK-NOT: Unknown command line argument
 # UNKNOWN:   for the --section-headers option: may only occur zero or one times!

llvm/test/tools/llvm-readobj/ELF/sections.test

@@ -10,16 +10,12 @@
 # RUN: llvm-readobj --sections %t64 > %t64.llvm.sections
 # RUN: llvm-readobj -S %t64 > %t64.llvm.upper.s
 # RUN: cmp %t64.llvm.sections %t64.llvm.upper.s
-# RUN: llvm-readobj -s %t64 > %t64.llvm.lower.s
-# RUN: cmp %t64.llvm.sections %t64.llvm.lower.s
 # RUN: llvm-readobj --section-headers %t64 > %t64.llvm.section-headers
 # RUN: cmp %t64.llvm.sections %t64.llvm.section-headers
 
 # RUN: llvm-readobj --sections %t32 > %t32.llvm.sections
 # RUN: llvm-readobj -S %t32 > %t32.llvm.upper.s
 # RUN: cmp %t32.llvm.sections %t32.llvm.upper.s
-# RUN: llvm-readobj -s %t32 > %t32.llvm.lower.s
-# RUN: cmp %t32.llvm.sections %t32.llvm.lower.s
 # RUN: llvm-readobj --section-headers %t32 > %t32.llvm.section-headers
 # RUN: cmp %t32.llvm.sections %t32.llvm.section-headers
 

llvm/test/tools/llvm-readobj/ELF/symbols.test

@@ -70,17 +70,13 @@
 # RUN: llvm-readobj --symbols %t64 > %t.symbols
 # RUN: llvm-readobj --syms %t64 > %t.syms
 # RUN: cmp %t.symbols %t.syms
-# RUN: llvm-readobj -t %t64 > %t.t
-# RUN: cmp %t.symbols %t.t
-# RUN: llvm-readelf -s --elf-output-style=LLVM %t64 > %t.lowers
-# RUN: cmp %t.symbols %t.lowers
+# RUN: llvm-readobj -s %t64 | diff %t.symbols -
+# RUN: llvm-readelf -s --elf-output-style=LLVM %t64 | diff %t.symbols -
 
 # RUN: llvm-readelf --symbols %t64 > %t.symbols.gnu
 # RUN: llvm-readelf --syms %t64 > %t.syms.gnu
 # RUN: cmp %t.symbols.gnu %t.syms.gnu
-
-## -s is an llvm-readobj option to dump sections.
-# RUN: llvm-readobj -s --elf-output-style=GNU %t64 | FileCheck %s --implicit-check-not="Symbol table"
+# RUN: llvm-readelf -s %t64 | diff %t.symbols.gnu -
 
 ## Case 3: Test that both regular and dynamic symbols are dumped when `--symbols` and `--dyn-symbols`
 ##         are specified together. Note that the order is different for different styles.

llvm/test/tools/llvm-readobj/basic.test

@@ -54,8 +54,6 @@ HELP: OVERVIEW: LLVM Object Reader
 OBJ: llvm-readobj{{.*}} [options] <input object files>
 ELF: llvm-readelf{{.*}} [options] <input object files>
 HELP: OPTIONS:
-OBJ: -s - Alias for --section-headers
-OBJ: -t - Alias for --symbols
-ELF: -s - Alias for --symbols
-ELF: -t - Alias for --section-details
+HELP -s - Alias for --symbols
+HELP -t - Alias for --section-details
 HELP: @FILE

llvm/test/tools/yaml2obj/ELF/duplicate-symbol-names.yaml

@@ -2,7 +2,7 @@
 ## containing symbols with duplicate names (but different name suffixes).
 
 # RUN: yaml2obj --docnum=1 %s -o %t1
-# RUN: llvm-readobj -t %t1 | FileCheck %s --check-prefix=CASE1
+# RUN: llvm-readobj --syms %t1 | FileCheck %s --check-prefix=CASE1
 
 # CASE1: Name: localfoo (1)
 # CASE1: Name: localfoo (1)

llvm/tools/llvm-readobj/llvm-readobj.cpp

@@ -142,6 +142,10 @@ namespace opts {
   // Also -t in llvm-readelf mode.
   cl::opt<bool> SectionDetails("section-details",
                                cl::desc("Display the section details"));
+  static cl::alias SectionDetailsShort("t",
+                                       cl::desc("Alias for --section-details"),
+                                       cl::aliasopt(SectionDetails),
+                                       cl::NotHidden);
 
   // --symbols
   // Also -s in llvm-readelf mode, or -t in llvm-readobj mode.
@@ -151,6 +155,9 @@ namespace opts {
                        "symbol table when using GNU output style for ELF"));
   cl::alias SymbolsGNU("syms", cl::desc("Alias for --symbols"),
                        cl::aliasopt(Symbols));
+  static cl::alias SymbolsShort("s", cl::desc("Alias for --symbols"),
+                                cl::aliasopt(Symbols), cl::NotHidden,
+                                cl::Grouping);
 
   // --dyn-symbols, --dyn-syms
   // Also --dt in llvm-readobj mode.
@@ -694,16 +701,6 @@ static void dumpInput(StringRef File, ScopedPrinter &Writer) {
 
 /// Registers aliases that should only be allowed by readobj.
 static void registerReadobjAliases() {
-  // -s has meant --sections for a very long time in llvm-readobj despite
-  // meaning --symbols in readelf.
-  static cl::alias SectionsShort("s", cl::desc("Alias for --section-headers"),
-                                 cl::aliasopt(opts::SectionHeaders),
-                                 cl::NotHidden);
-
-  // llvm-readelf reserves it for --section-details.
-  static cl::alias SymbolsShort("t", cl::desc("Alias for --symbols"),
-                                cl::aliasopt(opts::Symbols), cl::NotHidden);
-
   // The following two-letter aliases are only provided for readobj, as readelf
   // allows single-letter args to be grouped together.
   static cl::alias SectionRelocationsShort(
@@ -721,16 +718,6 @@ static void registerReadobjAliases() {
 
 /// Registers aliases that should only be allowed by readelf.
 static void registerReadelfAliases() {
-  // -s is here because for readobj it means --sections.
-  static cl::alias SymbolsShort("s", cl::desc("Alias for --symbols"),
-                                cl::aliasopt(opts::Symbols), cl::NotHidden,
-                                cl::Grouping);
-
-  // -t is here because for readobj it is an alias for --symbols.
-  static cl::alias SectionDetailsShort(
-      "t", cl::desc("Alias for --section-details"),
-      cl::aliasopt(opts::SectionDetails), cl::NotHidden);
-
   // Allow all single letter flags to be grouped together.
   for (auto &OptEntry : cl::getRegisteredOptions()) {
     StringRef ArgName = OptEntry.getKey();