[clang] [flang] [Flang] Add -ffast-real-mod back for further control of MOD optimizations (PR #167118)

[Tarun Prabhu via cfe-commits]

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@@ -1,24 +1,24 @@
-! RUN: %flang_fc1 -ffast-math -emit-mlir -o - %s | FileCheck %s --check-prefixes=CHECK%if target=x86_64{{.*}} %{,CHECK-KIND10%}%if flang-supports-f128-math %{,CHECK-KIND16%}
+! RUN: %flang_fc1 -ffast-real-mod -emit-mlir -o - %s | FileCheck %s --check-prefixes=CHECK-FRM%if target=x86_64{{.*}} %{,CHECK-FRM-KIND10%}%if flang-supports-f128-math %{,CHECK-FRM-KIND16%}
+! RUN: %flang_fc1 -ffast-math -emit-mlir -o - %s | FileCheck %s --check-prefixes=CHECK-FRM%if target=x86_64{{.*}} %{,CHECK-FRM-KIND10%}%if flang-supports-f128-math %{,CHECK-FRM-KIND16%}
 ! RUN: %flang_fc1 -ffast-math -fno-fast-real-mod -emit-mlir -o - %s | FileCheck %s --check-prefixes=CHECK-NFRM%if target=x86_64{{.*}} %{,CHECK-NFRM-KIND10%}%if flang-supports-f128-math %{,CHECK-NFRM-KIND16%}
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tarunprabhu wrote:

Do you think there is any advantage to writing a test for the case where `fno-fast-real-mod` is provided _without_ `-ffast-math`?

https://github.com/llvm/llvm-project/pull/167118