[clang] Clean up denormal handling with -ffp-model, -ffast-math, etc. (PR #89477)

[Andy Kaylor via cfe-commits]

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@@ -64,7 +64,8 @@
 
 // RUN: %clang -### -ffp-model=strict -fdenormal-fp-math=preserve-sign,preserve-sign -c %s 2>&1 \
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andykaylor wrote:

I didn't intend to change the logic of this test. The behavior here should be target-independent now.

https://github.com/llvm/llvm-project/pull/89477