[PATCH] D131469: [Clang] change default storing path of `-ftime-trace`

[dongjunduo via Phabricator via cfe-commits]

dongjunduo added inline comments.


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Comment at: clang/lib/Driver/Driver.cpp:4702
+
+  // Add or replace -ftime-trace<path>` to the correct one to all clang jobs
+  for (auto &J : C.getJobs()) {
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Whitney wrote:
> Do you mean Add or replace the modified `-ftime-trace=<path>` to all clang jobs?
Right


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Comment at: clang/lib/Driver/Driver.cpp:4739
+
+      // replace `-ftime-trace=<path>`
+      auto &JArgs = J.getArguments();
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Whitney wrote:
> should we also replace `-ftime-trace`?
The work before here is to infer the correct path to store the time-trace file.

After that, the <path> in `-ftime-trace=<path>` should be replaced by the infered correct path.

We do not need to replace `-ftime-trace` then.


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Comment at: clang/test/Driver/check-time-trace.cpp:4
+// RUN: %clangxx -ftime-trace -ftime-trace-granularity=0 -o %T/exe/check-time-trace %s
+// RUN: cat %T/exe/check-time-trace*.json \
+// RUN:   | %python -c 'import json, sys; json.dump(json.loads(sys.stdin.read()), sys.stdout, sort_keys=True, indent=2)' \
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Whitney wrote:
> what may be between `check-time-trace` and `.json`?
If we use `-ftime-trace` but no `-ftime-trace=<path>` to compile the source like "check-time-trace.cpp" to a executable file `check-time-trace`, the `check-time-trace.cpp` should be compiled to `check-time-trace-[random-string].o`, then linked to the `check-time-trace` by the linker. This random string is introduced by clang's own default logic.

The `-ftime-trace` records the time cost details of compilng source file to the object file (.cpp -> .o). If the time-trace file name isn't be specified, its default name is [object file's name].json, which is corresponding the object file.

Demo:

Cmd: `clang++ -ftime-trace -ftime-trace-granularity=0 -o check-time-trace check-time-trace.cpp`
Output: `check-time-trace`, `check-time-trace-a40601.json`


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D131469/new/

https://reviews.llvm.org/D131469