[clang] [PGO] Add a clang option -fprofile-continuous that enables continuous instrumentation profiling mode (PR #124353)

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,21 @@
+// 1) test on platforms that (do or do not) require runtime relocation
+//
+// RUN: %clang -target x86_64-darwin -fprofile-generate -fprofile-continuous -### -c %s 2>&1 | FileCheck %s --check-prefix=NO_RELOC
+// NO_RELOC: "-cc1" {{.*}} "-fprofile-continuous"
+// NO_RELOC-NOT: "-mllvm" "-runtime-counter-relocation"
+
+// RUN: %clang -target powerpc64-ibm-aix -fprofile-generate -fprofile-continuous -### -c %s 2>&1 | FileCheck %s --check-prefix=RELOC
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MaskRay wrote:

`--target=`

`-target ` has been deprecated for a long time.

https://github.com/llvm/llvm-project/pull/124353