[clang] [clang] Set FPOptions at the beginning of CompoundStmt (PR #111654)

[Serge Pavlov via cfe-commits]

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@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -ffast-math -ffp-contract=fast -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -ffast-math -ffp-contract=fast -emit-llvm -O2 -o - %s | FileCheck %s
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spavloff wrote:

Yes, this fact is reflected in #84648. Actually the problem is incorrect optimization caused by wrong fast-math flags.

Also your example cannot demonstrate the issue because it is C++ code. In C++ mode instructions like SelectInst or PHINode do not get fast-math flags.

https://github.com/llvm/llvm-project/pull/111654