[Remarks][Driver] Place temporary remark files next to temporary object files

On Darwin, when used for generating a linked binary from a source file
(through an intermediate object file), the driver will invoke `cc1` to
generate a temporary object file. The temporary remark file will now be
emitted next to the object file, which will then be picked up by
`dsymutil` and emitted in the .dSYM bundle.

This is available for all formats except YAML since by default, YAML
doesn't need a section and the remark file will be lost.

Author: francisvm

clang/docs/UsersManual.rst

@@ -355,28 +355,47 @@ output format of the diagnostics that it generates.
 
    where ``<base>`` is based on the output file of the compilation (whether
    it's explicitly specified through `-o` or not) when used with `-c` or `-S`.
-   In other cases, it's based on the input file's stem. For example:
+   For example:
 
    * ``clang -fsave-optimization-record -c in.c -o out.o`` will generate
      ``out.opt.yaml``
 
-   * ``clang -fsave-optimization-record in.c -o out`` will generate
+   * ``clang -fsave-optimization-record -c in.c `` will generate
      ``in.opt.yaml``
 
-   Compiling for multiple architectures will use the following scheme:
-
-   ``<base>-<arch>.opt.<format>``
-
-   Note that this is only allowed on Darwin platforms and is incompatible with
-   passing multiple ``-arch <arch>`` options.
-
    When targeting (Thin)LTO, the base is derived from the output filename, and
    the extension is not dropped.
 
    When targeting ThinLTO, the following scheme is used:
 
    ``<base>.opt.<format>.thin.<num>.<format>``
 
+   Darwin-only: when used for generating a linked binary from a source file
+   (through an intermediate object file), the driver will invoke `cc1` to
+   generate a temporary object file. The temporary remark file will be emitted
+   next to the object file, which will then be picked up by `dsymutil` and
+   emitted in the .dSYM bundle. This is available for all formats except YAML.
+
+   For example:
+
+   ``clang -fsave-optimization-record=bitstream in.c -o out`` will generate
+
+   * ``/var/folders/43/9y164hh52tv_2nrdxrj31nyw0000gn/T/a-9be59b.o``
+
+   * ``/var/folders/43/9y164hh52tv_2nrdxrj31nyw0000gn/T/a-9be59b.opt.bitstream``
+
+   * ``out``
+
+   * ``out.dSYM/Contents/Resources/Remarks/out``
+
+   Darwin-only: compiling for multiple architectures will use the following
+   scheme:
+
+   ``<base>-<arch>.opt.<format>``
+
+   Note that this is incompatible with passing the
+   :ref:`-foptimization-record-file <opt_foptimization-record-file>` option.
+
 .. _opt_foptimization-record-file:
 
 **-foptimization-record-file**

clang/lib/Driver/ToolChains/Clang.cpp

@@ -1444,7 +1444,12 @@ static bool checkRemarksOptions(const Driver &D, const ArgList &Args,
 
 static void renderRemarksOptions(const ArgList &Args, ArgStringList &CmdArgs,
                                  const llvm::Triple &Triple,
-                                 const InputInfo &Input, const JobAction &JA) {
+                                 const InputInfo &Input,
+                                 const InputInfo &Output, const JobAction &JA) {
+  StringRef Format = "yaml";
+  if (const Arg *A = Args.getLastArg(options::OPT_fsave_optimization_record_EQ))
+    Format = A->getValue();
+
   CmdArgs.push_back("-opt-record-file");
 
   const Arg *A = Args.getLastArg(options::OPT_foptimization_record_file_EQ);
@@ -1454,11 +1459,17 @@ static void renderRemarksOptions(const ArgList &Args, ArgStringList &CmdArgs,
     bool hasMultipleArchs =
         Triple.isOSDarwin() && // Only supported on Darwin platforms.
         Args.getAllArgValues(options::OPT_arch).size() > 1;
+
     SmallString<128> F;
 
     if (Args.hasArg(options::OPT_c) || Args.hasArg(options::OPT_S)) {
       if (Arg *FinalOutput = Args.getLastArg(options::OPT_o))
         F = FinalOutput->getValue();
+    } else {
+      if (Format != "yaml" && // For YAML, keep the original behavior.
+          Triple.isOSDarwin() && // Enable this only on darwin, since it's the only platform supporting .dSYM bundles.
+          Output.isFilename())
+        F = Output.getFilename();
     }
 
     if (F.empty()) {
@@ -1494,12 +1505,9 @@ static void renderRemarksOptions(const ArgList &Args, ArgStringList &CmdArgs,
       llvm::sys::path::replace_extension(F, OldExtension);
     }
 
-    std::string Extension = "opt.";
-    if (const Arg *A =
-            Args.getLastArg(options::OPT_fsave_optimization_record_EQ))
-      Extension += A->getValue();
-    else
-      Extension += "yaml";
+    SmallString<32> Extension;
+    Extension += "opt.";
+    Extension += Format;
 
     llvm::sys::path::replace_extension(F, Extension);
     CmdArgs.push_back(Args.MakeArgString(F));
@@ -1511,10 +1519,9 @@ static void renderRemarksOptions(const ArgList &Args, ArgStringList &CmdArgs,
     CmdArgs.push_back(A->getValue());
   }
 
-  if (const Arg *A =
-          Args.getLastArg(options::OPT_fsave_optimization_record_EQ)) {
+  if (!Format.empty()) {
     CmdArgs.push_back("-opt-record-format");
-    CmdArgs.push_back(A->getValue());
+    CmdArgs.push_back(Format.data());
   }
 }
 
@@ -5524,7 +5531,7 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
 
   // Remarks can be enabled with any of the `-f.*optimization-record.*` flags.
   if (willEmitRemarks(Args) && checkRemarksOptions(D, Args, Triple))
-    renderRemarksOptions(Args, CmdArgs, Triple, Input, JA);
+    renderRemarksOptions(Args, CmdArgs, Triple, Input, Output, JA);
 
   bool RewriteImports = Args.hasFlag(options::OPT_frewrite_imports,
                                      options::OPT_fno_rewrite_imports, false);

clang/test/Driver/darwin-opt-record.c

@@ -4,6 +4,7 @@
 // RUN: %clang -target x86_64-apple-darwin10 -### -c -o FOO -foptimization-record-file=tmp -arch x86_64 -arch x86_64h %s 2>&1 | FileCheck %s --check-prefix=CHECK-MULTIPLE-ARCH-ERROR
 // RUN: %clang -target x86_64-apple-darwin10 -### -o FOO -fsave-optimization-record %s 2>&1 | FileCheck %s --check-prefix=CHECK-DSYMUTIL-NO-G
 // RUN: %clang -target x86_64-apple-darwin10 -### -o FOO -g0 -fsave-optimization-record %s 2>&1 | FileCheck %s --check-prefix=CHECK-DSYMUTIL-G0
+// RUN: %clang -target x86_64-apple-darwin10 -### -o FOO -fsave-optimization-record=bitstream %s 2>&1 | FileCheck %s --check-prefix=CHECK-NO-G-PATH-BITSTREAM
 //
 // CHECK-MULTIPLE-ARCH: "-cc1"
 // CHECK-MULTIPLE-ARCH: "-opt-record-file" "FOO-x86_64.opt.yaml"
@@ -22,3 +23,9 @@
 // CHECK-DSYMUTIL-G0: "-cc1"
 // CHECK-DSYMUTIL-G0: ld
 // CHECK-DSYMUTIL-G0: dsymutil
+//
+// CHECK-NO-G-PATH-BITSTREAM: "-cc1"
+// CHECK-NO-G-PATH-BITSTREAM: "-opt-record-file" "[[OUTPATH:.*]].opt.bitstream"
+// CHECK-NO-G-PATH-BITSTREAM: "-o" "[[OUTPATH:.*]].o"
+// CHECK-NO-G-PATH-BITSTREAM: ld
+// CHECK-NO-G-PATH-BITSTREAM: dsymutil