[llvm-symbolizer] Allow more flexible usage of -e

[ikudrin]

Summary

'addr2line' allows -e to be grouped with other options; it also allows it to prefix the value. Thus, all the following usages are possible:

• addr2line -f -e <bin> <addr>
• addr2line -fe <bin> <addr>
• addr2line -f e<bin> <addr>
• addr2line -fe<bin> <addr>

This patch adds the same for llvm-symbolizer.

[jhenderson]

Do you think it's worth testing the behaviour of -e in the middle of a group of options e.g. "-Cefi"?

[ikudrin]

In D60196#1453050, @jhenderson wrote:

Do you think it's worth testing the behaviour of -e in the middle of a group of options e.g. "-Cefi"?

It's a negative scenario, right? Haven't we already checked that in CommandLineTest.GroupingWithValue?

[jhenderson]

In D60196#1453157, @ikudrin wrote:

In D60196#1453050, @jhenderson wrote:

Do you think it's worth testing the behaviour of -e in the middle of a group of options e.g. "-Cefi"?

It's a negative scenario, right? Haven't we already checked that in CommandLineTest.GroupingWithValue?

The issue is that that unit test only tests that options with the specific set of properties are handled in that way, but doesn't show that the -e option has those properties. I'm in two minds about it though, because it clearly takes a value. I guess I'm wondering how we know that "-Cefi" is/isn't equivalent to "-C -e=fi" without inspecting the code.

[ikudrin]

It looks like I've just forgotten to enable a prefix form for the switch. Does that resolve the doubts?

[jhenderson]

LGTM.

test/tools/llvm-symbolizer/flag-grouping.test

 RUN: llvm-symbolizer -apCi -obj=%p/Inputs/addr.exe < %p/Inputs/addr.inp | FileCheck %s
+RUN: llvm-symbolizer -apCie %p/Inputs/addr.exe < %p/Inputs/addr.inp | FileCheck %s
+RUN: llvm-symbolizer -apCie=%p/Inputs/addr.exe < %p/Inputs/addr.inp | FileCheck %s
 
 CHECK: some text
 CHECK: 0x40054d: inctwo
 CHECK: (inlined by) inc
 CHECK  (inlined by) main
 CHECK: some text2

tools/llvm-symbolizer/llvm-symbolizer.cpp

 // -obj, -exe, -e
 static cl::opt<std::string>
 ClBinaryName("obj", cl::init(""),
              cl::desc("Path to object file to be symbolized (if not provided, "
                       "object file should be specified for each input line)"));
 static cl::alias
 ClBinaryNameAliasExe("exe", cl::desc("Alias for -obj"),
                      cl::NotHidden, cl::aliasopt(ClBinaryName));
-static cl::alias
-ClBinaryNameAliasE("e", cl::desc("Alias for -obj"),
-                   cl::NotHidden, cl::aliasopt(ClBinaryName));
-
+static cl::alias ClBinaryNameAliasE("e", cl::desc("Alias for -obj"),
+                                    cl::Grouping, cl::NotHidden,
+                                    cl::aliasopt(ClBinaryName));
 
 static cl::opt<std::string>
     ClDwpName("dwp", cl::init(""),
               cl::desc("Path to DWP file to be use for any split CUs"));
 
 static cl::list<std::string>
 ClDsymHint("dsym-hint", cl::ZeroOrMore,
            cl::desc("Path to .dSYM bundles to search for debug info for the "