[Driver][SamplePGO] Enable -fsample-profile-use-profi (#146795)

Since profile inference improves sample coverage, it should be turned on by default.

Author: nilanjana87

clang/lib/Driver/ToolChains/Clang.cpp

@@ -6265,7 +6265,7 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
 
   if (getLastProfileSampleUseArg(Args) &&
       Args.hasFlag(options::OPT_fsample_profile_use_profi,
-                   options::OPT_fno_sample_profile_use_profi, false)) {
+                   options::OPT_fno_sample_profile_use_profi, true)) {
     CmdArgs.push_back("-mllvm");
     CmdArgs.push_back("-sample-profile-use-profi");
   }

clang/test/Driver/pgo-sample-use-profi.c

@@ -1,11 +1,11 @@
 /// Test if profi flag is enabled/disabled correctly based on user-specified configuration.
-/// Ensure that profi flag is disabled by default
+/// Ensure that profi flag is enabled by default
 
-// RUN: %clang --target=x86_64 -c -fprofile-sample-use=/dev/null -### %s 2>&1 | FileCheck %s --check-prefixes=CHECK-NO-PROFI
+// RUN: %clang --target=x86_64 -c -fprofile-sample-use=/dev/null -### %s 2>&1 | FileCheck %s
 // RUN: %clang --target=x86_64 -c -fsample-profile-use-profi -fprofile-sample-use=/dev/null -### %s 2>&1 | FileCheck %s
 // RUN: %clang --target=x86_64 -c -fno-sample-profile-use-profi -fsample-profile-use-profi -fprofile-sample-use=/dev/null -### %s 2>&1 | FileCheck %s
 
-// RUN: %clang --target=AArch64 -c -fprofile-sample-use=/dev/null -### %s 2>&1 | FileCheck %s --check-prefixes=CHECK-NO-PROFI
+// RUN: %clang --target=AArch64 -c -fprofile-sample-use=/dev/null -### %s 2>&1 | FileCheck %s
 // RUN: %clang --target=AArch64 -c -fsample-profile-use-profi -fprofile-sample-use=/dev/null -### %s 2>&1 | FileCheck %s
 // RUN: %clang --target=AArch64 -c -fno-sample-profile-use-profi -fsample-profile-use-profi -fprofile-sample-use=/dev/null -### %s 2>&1 | FileCheck %s