[clang] [Driver] Introduce ffp-model=aggressive (PR #100453)

[Fangrui Song via cfe-commits]

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@@ -163,23 +183,41 @@
 // CHECK-FEB-IGNORE: "-fno-rounding-math"
 // CHECK-FEB-IGNORE: "-ffp-exception-behavior=ignore"
 
-// RUN: %clang -### -nostdinc -Werror -ffast-math -ffp-model=fast -c %s 2>&1 \
+// RUN: %clang -### -nostdinc -Werror -ffast-math -ffp-model=aggressive -c %s 2>&1 \
+// RUN:   | FileCheck --check-prefix=CHECK-FASTMATH-FPM-AGGR %s
+// CHECK-FASTMATH-FPM-AGGR: "-cc1"
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MaskRay wrote:

perhaps pack some options on the same line to show that they are adjacent (no other option in between)

If this extra check isn't important, I expect at least `-SAME:`

https://github.com/llvm/llvm-project/pull/100453