[clang] [flang]Add vscale argument parsing (PR #67676)

[Andrzej Warzyński via cfe-commits]

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@@ -0,0 +1,55 @@
+! -----------------------------------------------------------------------------
+! Tests for the -msve-vector-bits flag (taken from the clang test)
+! -----------------------------------------------------------------------------
+
+! RUN: %flang -c %s -### --target=aarch64-none-linux-gnu -march=armv8-a+sve \
+! RUN:  -msve-vector-bits=128 2>&1 | FileCheck --check-prefix=CHECK-128 %s
+! RUN: %flang -c %s -### --target=aarch64-none-linux-gnu -march=armv8-a+sve \
+! RUN:  -msve-vector-bits=256 2>&1 | FileCheck --check-prefix=CHECK-256 %s
+! RUN: %flang -c %s -### --target=aarch64-none-linux-gnu -march=armv8-a+sve \
+! RUN:  -msve-vector-bits=512 2>&1 | FileCheck --check-prefix=CHECK-512 %s
+! RUN: %flang -c %s -### --target=aarch64-none-linux-gnu -march=armv8-a+sve \
+! RUN:  -msve-vector-bits=1024 2>&1 | FileCheck --check-prefix=CHECK-1024 %s
+! RUN: %flang -c %s -### --target=aarch64-none-linux-gnu -march=armv8-a+sve \
+! RUN:  -msve-vector-bits=2048 2>&1 | FileCheck --check-prefix=CHECK-2048 %s
+! RUN: %flang -c %s -### --target=aarch64-none-linux-gnu -march=armv8-a+sve \
+! RUN:  -msve-vector-bits=128+ 2>&1 | FileCheck --check-prefix=CHECK-128P %s
+! RUN: %flang -c %s -### --target=aarch64-none-linux-gnu -march=armv8-a+sve \
+! RUN:  -msve-vector-bits=256+ 2>&1 | FileCheck --check-prefix=CHECK-256P %s
+! RUN: %flang -c %s -### --target=aarch64-none-linux-gnu -march=armv8-a+sve \
+! RUN:  -msve-vector-bits=512+ 2>&1 | FileCheck --check-prefix=CHECK-512P %s
+! RUN: %flang -c %s -### --target=aarch64-none-linux-gnu -march=armv8-a+sve \
+! RUN:  -msve-vector-bits=1024+ 2>&1 | FileCheck --check-prefix=CHECK-1024P %s
+! RUN: %flang -c %s -### --target=aarch64-none-linux-gnu -march=armv8-a+sve \
+! RUN:  -msve-vector-bits=2048+ 2>&1 | FileCheck --check-prefix=CHECK-2048P %s
+! RUN: %flang -c %s -### --target=aarch64-none-linux-gnu -march=armv8-a+sve \
+! RUN:  -msve-vector-bits=scalable 2>&1 | FileCheck --check-prefix=CHECK-SCALABLE %s
+
+! CHECK-128: "-mvscale-max=1" "-mvscale-min=1"
----------------
banach-space wrote:

> So you're saying we should check that it's not catching some other - preprocessor, linker or something else that may have got hold of the "right" command-line argument?

Indeed. Also, as a documentation for our future selves. It won't hurt, but could make our lives easier when re-visiting this in e.g. 6 months time :) 

This is a nit, feel free to land as is 👍🏻 Thank you :)

https://github.com/llvm/llvm-project/pull/67676