Revert "Revert r305164/5/7."

Restore the `-gz` option to the driver with some minor tweaks to handle
the additional case for `-Wa,--compress-debug-sections`.

This intends to make the compression of the debug information
controllable from the driver.  The following is the behaviour:

  -gz           enable compression (ambiguous for format, will default to zlib-gnu)
  -gz=none      disable compression
  -gz=zlib-gnu  enable compression (deprecated GNU style zlib compression)
  -gz=zlib      enable compression (zlib based compression)

Although -Wa,-compress-debug-sections works, it should be discouraged
when using the driver to invoke the assembler.  However, we permit the
assembler to accept the GNU as style argument --compress-debug-sections
to maintain compatibility.

Note, -gz/-gz= does *NOT* imply -g.  That is, you need to additionally
specific -g for debug information to be generated.

llvm-svn: 306115

clang/include/clang/Driver/CC1Options.td

@@ -134,7 +134,6 @@ def migrator_no_finalize_removal : Flag<["-"], "no-finalize-removal">,
 //===----------------------------------------------------------------------===//
 
 let Flags = [CC1Option, CC1AsOption, NoDriverOption] in {
-
 def debug_info_kind_EQ : Joined<["-"], "debug-info-kind=">;
 def debug_info_macro : Flag<["-"], "debug-info-macro">,
   HelpText<"Emit macro debug information">;
@@ -144,14 +143,16 @@ def fdebug_compilation_dir : Separate<["-"], "fdebug-compilation-dir">,
   HelpText<"The compilation directory to embed in the debug info.">;
 def dwarf_debug_flags : Separate<["-"], "dwarf-debug-flags">,
   HelpText<"The string to embed in the Dwarf debug flags record.">;
+def compress_debug_sections : Flag<["-", "--"], "compress-debug-sections">,
+    HelpText<"DWARF debug sections compression">;
+def compress_debug_sections_EQ : Flag<["-"], "compress-debug-sections=">,
+    HelpText<"DWARF debug sections compression type">;
 def mno_exec_stack : Flag<["-"], "mnoexecstack">,
   HelpText<"Mark the file as not needing an executable stack">;
 def massembler_fatal_warnings : Flag<["-"], "massembler-fatal-warnings">,
   HelpText<"Make assembler warnings fatal">;
 def mrelax_relocations : Flag<["--"], "mrelax-relocations">,
     HelpText<"Use relaxable elf relocations">;
-def compress_debug_sections : Flag<["-"], "compress-debug-sections">,
-    HelpText<"Compress DWARF debug sections using zlib">;
 def msave_temp_labels : Flag<["-"], "msave-temp-labels">,
   HelpText<"Save temporary labels in the symbol table. "
            "Note this may change .s semantics and shouldn't generally be used "

clang/include/clang/Driver/Options.td

@@ -1563,6 +1563,10 @@ def gdwarf_aranges : Flag<["-"], "gdwarf-aranges">, Group<g_flags_Group>;
 def gmodules : Flag <["-"], "gmodules">, Group<gN_Group>,
   HelpText<"Generate debug info with external references to clang modules"
            " or precompiled headers">;
+def gz : Flag<["-"], "gz">, Group<g_flags_Group>,
+    HelpText<"DWARF debug sections compression type">;
+def gz_EQ : Joined<["-"], "gz=">, Group<g_flags_Group>,
+    HelpText<"DWARF debug sections compression type">;
 def headerpad__max__install__names : Joined<["-"], "headerpad_max_install_names">;
 def help : Flag<["-", "--"], "help">, Flags<[CC1Option,CC1AsOption]>,
   HelpText<"Display available options">;

clang/lib/Driver/ToolChains/Clang.cpp

@@ -910,6 +910,37 @@ static void RenderDebugEnablingArgs(const ArgList &Args, ArgStringList &CmdArgs,
   }
 }
 
+static void RenderDebugInfoCompressionArgs(const ArgList &Args,
+                                           ArgStringList &CmdArgs,
+                                           const Driver &D) {
+  const Arg *A = Args.getLastArg(options::OPT_gz, options::OPT_gz_EQ);
+  if (!A)
+    return;
+
+  if (A->getOption().getID() == options::OPT_gz) {
+    if (llvm::zlib::isAvailable())
+      CmdArgs.push_back("-compress-debug-sections");
+    else
+      D.Diag(diag::warn_debug_compression_unavailable);
+    return;
+  }
+
+  StringRef Value = A->getValue();
+  if (Value == "none") {
+    CmdArgs.push_back("-compress-debug-sections=none");
+  } else if (Value == "zlib" || Value == "zlib-gnu") {
+    if (llvm::zlib::isAvailable()) {
+      CmdArgs.push_back(
+          Args.MakeArgString("-compress-debug-sections=" + Twine(Value)));
+    } else {
+      D.Diag(diag::warn_debug_compression_unavailable);
+    }
+  } else {
+    D.Diag(diag::err_drv_unsupported_option_argument)
+        << A->getOption().getName() << Value;
+  }
+}
+
 static const char *RelocationModelName(llvm::Reloc::Model Model) {
   switch (Model) {
   case llvm::Reloc::Static:
@@ -1747,10 +1778,6 @@ static void CollectArgsForIntegratedAssembler(Compilation &C,
   // arg after parsing the '-I' arg.
   bool TakeNextArg = false;
 
-  // When using an integrated assembler, translate -Wa, and -Xassembler
-  // options.
-  bool CompressDebugSections = false;
-
   bool UseRelaxRelocations = ENABLE_X86_RELAX_RELOCATIONS;
   const char *MipsTargetFeature = nullptr;
   for (const Arg *A :
@@ -1825,12 +1852,11 @@ static void CollectArgsForIntegratedAssembler(Compilation &C,
         CmdArgs.push_back("-massembler-fatal-warnings");
       } else if (Value == "--noexecstack") {
         CmdArgs.push_back("-mnoexecstack");
-      } else if (Value == "-compress-debug-sections" ||
+      } else if (Value.startswith("-compress-debug-sections") ||
-                 Value == "--compress-debug-sections") {
+                 Value.startswith("--compress-debug-sections") ||
-        CompressDebugSections = true;
+                 Value == "-nocompress-debug-sections" ||
-      } else if (Value == "-nocompress-debug-sections" ||
                  Value == "--nocompress-debug-sections") {
-        CompressDebugSections = false;
+        CmdArgs.push_back(Value.data());
       } else if (Value == "-mrelax-relocations=yes" ||
                  Value == "--mrelax-relocations=yes") {
         UseRelaxRelocations = true;
@@ -1883,12 +1909,6 @@ static void CollectArgsForIntegratedAssembler(Compilation &C,
       }
     }
   }
-  if (CompressDebugSections) {
-    if (llvm::zlib::isAvailable())
-      CmdArgs.push_back("-compress-debug-sections");
-    else
-      D.Diag(diag::warn_debug_compression_unavailable);
-  }
   if (UseRelaxRelocations)
     CmdArgs.push_back("--mrelax-relocations");
   if (MipsTargetFeature != nullptr) {
@@ -2824,6 +2844,8 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     CmdArgs.push_back("-generate-type-units");
   }
 
+  RenderDebugInfoCompressionArgs(Args, CmdArgs, D);
+
   bool UseSeparateSections = isUseSeparateSections(Triple);
 
   if (Args.hasFlag(options::OPT_ffunction_sections,
@@ -4927,6 +4949,7 @@ void ClangAs::ConstructJob(Compilation &C, const JobAction &JA,
 
   const llvm::Triple &Triple = getToolChain().getEffectiveTriple();
   const std::string &TripleStr = Triple.getTriple();
+  const auto &D = getToolChain().getDriver();
 
   // Don't warn about "clang -w -c foo.s"
   Args.ClaimAllArgs(options::OPT_w);
@@ -5014,6 +5037,8 @@ void ClangAs::ConstructJob(Compilation &C, const JobAction &JA,
   }
   RenderDebugEnablingArgs(Args, CmdArgs, DebugInfoKind, DwarfVersion,
                           llvm::DebuggerKind::Default);
+  RenderDebugInfoCompressionArgs(Args, CmdArgs, D);
+
 
   // Handle -fPIC et al -- the relocation-model affects the assembler
   // for some targets.

clang/lib/Driver/ToolChains/Gnu.cpp

@@ -650,6 +650,8 @@ void tools::gnutools::Assembler::ConstructJob(Compilation &C,
                                               const InputInfoList &Inputs,
                                               const ArgList &Args,
                                               const char *LinkingOutput) const {
+  const auto &D = getToolChain().getDriver();
+
   claimNoWarnArgs(Args);
 
   ArgStringList CmdArgs;
@@ -660,6 +662,23 @@ void tools::gnutools::Assembler::ConstructJob(Compilation &C,
   std::tie(RelocationModel, PICLevel, IsPIE) =
       ParsePICArgs(getToolChain(), Args);
 
+  if (const Arg *A = Args.getLastArg(options::OPT_gz, options::OPT_gz_EQ)) {
+    if (A->getOption().getID() == options::OPT_gz) {
+      CmdArgs.push_back("-compress-debug-sections");
+    } else {
+      StringRef Value = A->getValue();
+      if (Value == "none") {
+        CmdArgs.push_back("-compress-debug-sections=none");
+      } else if (Value == "zlib" || Value == "zlib-gnu") {
+        CmdArgs.push_back(
+            Args.MakeArgString("-compress-debug-sections=" + Twine(Value)));
+      } else {
+        D.Diag(diag::err_drv_unsupported_option_argument)
+            << A->getOption().getName() << Value;
+      }
+    }
+  }
+
   switch (getToolChain().getArch()) {
   default:
     break;

clang/lib/Frontend/CompilerInvocation.cpp

@@ -745,9 +745,22 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   Opts.InstrumentForProfiling = Args.hasArg(OPT_pg);
   Opts.CallFEntry = Args.hasArg(OPT_mfentry);
   Opts.EmitOpenCLArgMetadata = Args.hasArg(OPT_cl_kernel_arg_info);
-  // TODO: map this from -gz in the driver and give it a named value
+
-  if (Args.hasArg(OPT_compress_debug_sections))
+  if (const Arg *A = Args.getLastArg(OPT_compress_debug_sections,
+                                     OPT_compress_debug_sections_EQ)) {
+    if (A->getOption().getID() == OPT_compress_debug_sections) {
+      // TODO: be more clever about the compression type auto-detection
       Opts.setCompressDebugSections(llvm::DebugCompressionType::GNU);
+    } else {
+      auto DCT = llvm::StringSwitch<llvm::DebugCompressionType>(A->getValue())
+                     .Case("none", llvm::DebugCompressionType::None)
+                     .Case("zlib", llvm::DebugCompressionType::Z)
+                     .Case("zlib-gnu", llvm::DebugCompressionType::GNU)
+                     .Default(llvm::DebugCompressionType::None);
+      Opts.setCompressDebugSections(DCT);
+    }
+  }
+
   Opts.RelaxELFRelocations = Args.hasArg(OPT_mrelax_relocations);
   Opts.DebugCompilationDir = Args.getLastArgValue(OPT_fdebug_compilation_dir);
   for (auto A : Args.filtered(OPT_mlink_bitcode_file, OPT_mlink_cuda_bitcode)) {

clang/test/Driver/compress-noias.c

@@ -0,0 +1,37 @@
+// REQUIRES: zlib
+// REQUIRES: x86-registered-target
+
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -Wa,-compress-debug-sections -c %s 2>&1 | FileCheck -check-prefix CHECK-_COMPRESS_DEBUG_SECTIONS %s
+// CHECK-_COMPRESS_DEBUG_SECTIONS: "-compress-debug-sections"
+
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -Wa,--compress-debug-sections -c %s 2>&1 | FileCheck -check-prefix CHECK-__COMPRESS_DEBUG_SECTIONS %s
+// CHECK-__COMPRESS_DEBUG_SECTIONS: "--compress-debug-sections"
+
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -Wa,--compress-debug-sections -Wa,--nocompress-debug-sections -c %s 2>&1 | FileCheck -check-prefix CHECK-POSNEG %s
+// CHECK-POSNEG: "--compress-debug-sections"
+// CHECK-POSNEG: "--nocompress-debug-sections"
+
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -Wa,-compress-debug-sections -Wa,--compress-debug-sections -c %s 2>&1 | FileCheck -check-prefix CHECK-MULTIPLE %s
+// CHECK-MULTIPLE: "-compress-debug-sections"
+// CHECK-MULTIPLE: "--compress-debug-sections"
+
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ %s
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ %s
+// CHECK-OPT_GZ: "-compress-debug-sections"
+
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=none -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_NONE %s
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=none -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_NONE %s
+// CHECK-OPT_GZ_EQ_NONE: "-compress-debug-sections=none"
+
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=zlib -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB %s
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=zlib -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB %s
+// CHECK-OPT_GZ_EQ_ZLIB: "-compress-debug-sections=zlib"
+
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=zlib-gnu -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB_GNU %s
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=zlib-gnu -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB_GNU %s
+// CHECK-OPT_GZ_EQ_ZLIB_GNU: "-compress-debug-sections=zlib-gnu"
+
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=invalid -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_INVALID %s
+// RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=invalid -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_INVALID %s
+// CHECK-OPT_GZ_EQ_INVALID: error: unsupported argument 'invalid' to option 'gz='
+

clang/test/Driver/compress.c

@@ -1,8 +1,36 @@
-// RUN: %clang -### -c -integrated-as -Wa,-compress-debug-sections %s 2>&1 | FileCheck --check-prefix=COMPRESS_DEBUG %s
-// RUN: %clang -### -c -integrated-as -Wa,--compress-debug-sections %s 2>&1 | FileCheck --check-prefix=COMPRESS_DEBUG %s
 // REQUIRES: zlib
 
-// COMPRESS_DEBUG: "-compress-debug-sections"
+// RUN: %clang -### -fintegrated-as -Wa,-compress-debug-sections -c %s 2>&1 | FileCheck -check-prefix CHECK-_COMPRESS_DEBUG_SECTIONS %s
+// CHECK-_COMPRESS_DEBUG_SECTIONS: "-compress-debug-sections"
+
+// RUN: %clang -### -fintegrated-as -Wa,--compress-debug-sections -c %s 2>&1 | FileCheck -check-prefix CHECK-__COMPRESS_DEBUG_SECTIONS %s
+// CHECK-__COMPRESS_DEBUG_SECTIONS: "--compress-debug-sections"
+
+// RUN: %clang -### -fintegrated-as -Wa,--compress-debug-sections -Wa,--nocompress-debug-sections -c %s 2>&1 | FileCheck -check-prefix CHECK-POSNEG %s
+// CHECK-POSNEG: "--compress-debug-sections"
+// CHECK-POSNEG: "--nocompress-debug-sections"
+
+// RUN: %clang -### -fintegrated-as -Wa,-compress-debug-sections -Wa,--compress-debug-sections -c %s 2>&1 | FileCheck -check-prefix CHECK-MULTIPLE %s
+// CHECK-MULTIPLE: "-compress-debug-sections"
+// CHECK-MULTIPLE: "--compress-debug-sections"
+
+// RUN: %clang -### -fintegrated-as -gz -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ %s
+// RUN: %clang -### -fintegrated-as -gz -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ %s
+// CHECK-OPT_GZ: "-compress-debug-sections"
+
+// RUN: %clang -### -fintegrated-as -gz=none -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_NONE %s
+// RUN: %clang -### -fintegrated-as -gz=none -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_NONE %s
+// CHECK-OPT_GZ_EQ_NONE: "-compress-debug-sections=none"
+
+// RUN: %clang -### -fintegrated-as -gz=zlib -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB %s
+// RUN: %clang -### -fintegrated-as -gz=zlib -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB %s
+// CHECK-OPT_GZ_EQ_ZLIB: "-compress-debug-sections=zlib"
+
+// RUN: %clang -### -fintegrated-as -gz=zlib-gnu -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB_GNU %s
+// RUN: %clang -### -fintegrated-as -gz=zlib-gnu -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB_GNU %s
+// CHECK-OPT_GZ_EQ_ZLIB_GNU: "-compress-debug-sections=zlib-gnu"
+
+// RUN: %clang -### -fintegrated-as -gz=invalid -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_INVALID %s
+// RUN: %clang -### -fintegrated-as -gz=invalid -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_INVALID %s
+// CHECK-OPT_GZ_EQ_INVALID: error: unsupported argument 'invalid' to option 'gz='
 
-// RUN: %clang -### -c -integrated-as -Wa,--compress-debug-sections -Wa,--nocompress-debug-sections %s 2>&1 | FileCheck --check-prefix=NOCOMPRESS_DEBUG %s
-// NOCOMPRESS_DEBUG-NOT: "-compress-debug-sections"

clang/test/Driver/nozlibcompress.c

@@ -1,6 +1,7 @@
-// RUN: %clang -c %s -Wa,--compress-debug-sections 2>&1 | FileCheck %s
-// RUN: %clang -c %s -Wa,--compress-debug-sections -Wa,--nocompress-debug-sections 2>&1 | FileCheck --allow-empty --check-prefix=NOWARN %s
 // REQUIRES: nozlib
 
-// CHECK: warning: cannot compress debug sections (zlib not installed)
+// RUN: %clang -fintegrated-as -gz -c %s 2>&1 | FileCheck %s -check-prefix CHECK-WARN
-// NOWARN-NOT: warning: cannot compress debug sections (zlib not installed)
+// RUN: %clang -fintegrated-as -gz=none -c %s 2>&1 | FileCheck -allow-empty -check-prefix CHECK-NOWARN %s
+
+// CHECK-WARN: warning: cannot compress debug sections (zlib not installed)
+// CHECK-NOWARN-NOT: warning: cannot compress debug sections (zlib not installed)

clang/test/Misc/cc1as-compress.s

@@ -0,0 +1,8 @@
+// REQUIRES: zlib
+// REQUIRES: x86-registered-target
+
+// RUN: %clang -cc1as -triple i686 --compress-debug-sections -filetype asm %s -o /dev/null 2>&1 | FileCheck -allow-empty %s
+// RUN: %clang -cc1as -triple i686 -compress-debug-sections -filetype asm %s -o /dev/null 2>&1 | FileCheck -allow-empty %s
+
+// CHECK-NOT: error: unknown argument:
+

clang/tools/driver/cc1as_main.cpp

@@ -202,9 +202,22 @@ bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
   Opts.SaveTemporaryLabels = Args.hasArg(OPT_msave_temp_labels);
   // Any DebugInfoKind implies GenDwarfForAssembly.
   Opts.GenDwarfForAssembly = Args.hasArg(OPT_debug_info_kind_EQ);
-  // TODO: base this on -gz instead
+
-  if (Args.hasArg(OPT_compress_debug_sections))
+  if (const Arg *A = Args.getLastArg(OPT_compress_debug_sections,
+                                     OPT_compress_debug_sections_EQ)) {
+    if (A->getOption().getID() == OPT_compress_debug_sections) {
+      // TODO: be more clever about the compression type auto-detection
       Opts.CompressDebugSections = llvm::DebugCompressionType::GNU;
+    } else {
+      Opts.CompressDebugSections =
+          llvm::StringSwitch<llvm::DebugCompressionType>(A->getValue())
+              .Case("none", llvm::DebugCompressionType::None)
+              .Case("zlib", llvm::DebugCompressionType::Z)
+              .Case("zlib-gnu", llvm::DebugCompressionType::GNU)
+              .Default(llvm::DebugCompressionType::None);
+    }
+  }
+
   Opts.RelaxELFRelocations = Args.hasArg(OPT_mrelax_relocations);
   Opts.DwarfVersion = getLastArgIntValue(Args, OPT_dwarf_version_EQ, 2, Diags);
   Opts.DwarfDebugFlags = Args.getLastArgValue(OPT_dwarf_debug_flags);