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

[Wael Yehia via cfe-commits]

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@@ -0,0 +1,16 @@
+// RUN: %clang %s -S -emit-llvm -fprofile-generate -fprofile-continuous -o - | FileCheck %s --check-prefix=IRPGO
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w2yehia wrote:

In this test, I'm testing both the driver (lines 4,5,8) and the clang codegen (lines 1,2,3,6).
Should I split it into 2 files, one for each stage?

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