[clang] [flang] [flang] Add -f[no-]slp-vectorize flags (PR #132801)

[Tom Eccles via cfe-commits]

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@@ -0,0 +1,10 @@
+! RUN: %flang -### -S -fslp-vectorize %s 2>&1 | FileCheck -check-prefix=CHECK-SLP-VECTORIZE %s
+! RUN: %flang -### -S -fno-slp-vectorize %s 2>&1 | FileCheck -check-prefix=CHECK-NO-SLP-VECTORIZE %s
+! RUN: %flang -### -S -O1 %s 2>&1 | FileCheck -check-prefix=CHECK-NO-SLP-VECTORIZE %s
+! RUN: %flang -### -S -O2 %s 2>&1 | FileCheck -check-prefix=CHECK-SLP-VECTORIZE %s
+! RUN: %flang -### -S -O3 %s 2>&1 | FileCheck -check-prefix=CHECK-SLP-VECTORIZE %s
+! CHECK-SLP-VECTORIZE: "-vectorize-slp"
+! CHECK-NO-SLP-VECTORIZE-NOT: "-no-vectorize-slp"
+
+program test
+end program
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tblah wrote:

Please could you add a test to see if this is passed correctly to the middle end? 

E.g. you could test whether `flang -mllvm -print-pipeline-passes` contains "slp-vectorizer"

https://github.com/llvm/llvm-project/pull/132801