implement -ftabstop=width, patch by Christian Adåker

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@93078 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Driver/CC1Options.td

@@ -178,6 +178,8 @@ def fdiagnostics_print_source_range_info : Flag<"-fdiagnostics-print-source-rang
   HelpText<"Print source range spans in numeric form">;
 def fdiagnostics_show_option : Flag<"-fdiagnostics-show-option">,
   HelpText<"Print diagnostic name with mappable diagnostics">;
+def ftabstop : Separate<"-ftabstop">, MetaVarName<"<N>">,
+  HelpText<"Set the tab stop distance.">;
 def fmessage_length : Separate<"-fmessage-length">, MetaVarName<"<N>">,
   HelpText<"Format message diagnostics so that they fit within N columns or fewer, when possible.">;
 def fcolor_diagnostics : Flag<"-fcolor-diagnostics">,

include/clang/Driver/Options.td

@@ -345,6 +345,7 @@ def fstack_protector_all : Flag<"-fstack-protector-all">, Group<f_Group>;
 def fstack_protector : Flag<"-fstack-protector">, Group<f_Group>;
 def fstrict_aliasing : Flag<"-fstrict-aliasing">, Group<clang_ignored_f_Group>;
 def fsyntax_only : Flag<"-fsyntax-only">, Flags<[DriverOption]>;
+def ftabstop_EQ : Joined<"-ftabstop=">, Group<f_Group>;
 def ftemplate_depth_ : Joined<"-ftemplate-depth-">, Group<f_Group>;
 def fterminated_vtables : Flag<"-fterminated-vtables">, Group<f_Group>;
 def ftime_report : Flag<"-ftime-report">, Group<f_Group>;

include/clang/Frontend/DiagnosticOptions.h

@@ -35,6 +35,9 @@ public:
                                  /// diagnostics, indicated by markers in the
                                  /// input source file.
 
+  /// The distance between tab stops.
+  unsigned TabStop;
+
   /// Column limit for formatting message diagnostics, or 0 if unused.
   unsigned MessageLength;
 
@@ -49,6 +52,7 @@ public:
 public:
   DiagnosticOptions() {
     IgnoreWarnings = 0;
+    TabStop = 8;
     MessageLength = 0;
     NoRewriteMacros = 0;
     Pedantic = 0;

lib/Driver/Tools.cpp

@@ -935,6 +935,11 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     CmdArgs.push_back(A->getValue(Args));
   }
 
+  if (Arg *A = Args.getLastArg(options::OPT_ftabstop_EQ)) {
+    CmdArgs.push_back("-ftabstop");
+    CmdArgs.push_back(A->getValue(Args));
+  }
+
   // Pass -fmessage-length=.
   CmdArgs.push_back("-fmessage-length");
   if (Arg *A = Args.getLastArg(options::OPT_fmessage_length_EQ)) {

lib/Frontend/CompilerInvocation.cpp

@@ -222,6 +222,10 @@ static void DiagnosticOptsToArgs(const DiagnosticOptions &Opts,
     Res.push_back("-verify");
   if (Opts.ShowOptionNames)
     Res.push_back("-fdiagnostics-show-option");
+  if (Opts.TabStop != 8) {
+    Res.push_back("-ftabstop");
+    Res.push_back(llvm::utostr(Opts.TabStop));
+  }
   if (Opts.MessageLength) {
     Res.push_back("-fmessage-length");
     Res.push_back(llvm::utostr(Opts.MessageLength));
@@ -804,6 +808,7 @@ static void ParseDiagnosticArgs(DiagnosticOptions &Opts, ArgList &Args,
   Opts.ShowOptionNames = Args.hasArg(OPT_fdiagnostics_show_option);
   Opts.ShowSourceRanges = Args.hasArg(OPT_fdiagnostics_print_source_range_info);
   Opts.VerifyDiagnostics = Args.hasArg(OPT_verify);
+  Opts.TabStop = getLastArgIntValue(Args, OPT_ftabstop, 8, Diags);
   Opts.MessageLength = getLastArgIntValue(Args, OPT_fmessage_length, 0, Diags);
   Opts.DumpBuildInformation = getLastArgValue(Args, OPT_dump_build_information);
   Opts.Warnings = getAllArgValues(Args, OPT_W);

lib/Frontend/TextDiagnosticPrinter.cpp

@@ -378,9 +378,10 @@ void TextDiagnosticPrinter::EmitCaretDiagnostic(SourceLocation Loc,
     // Replace this tab with at least one space.
     SourceLine[i] = ' ';
 
+    unsigned TabStop = DiagOpts->TabStop > 0 ? DiagOpts->TabStop : 8;
     // Compute the number of spaces we need to insert.
-    unsigned NumSpaces = ((i+8)&~7) - (i+1);
-    assert(NumSpaces < 8 && "Invalid computation of space amt");
+    unsigned NumSpaces = ((i+TabStop)/TabStop * TabStop) - (i+1);
+    assert(NumSpaces < TabStop && "Invalid computation of space amt");
 
     // Insert spaces into the SourceLine.
     SourceLine.insert(i+1, NumSpaces, ' ');