[Mlir-commits] [mlir] [mlir][test] Make SME e2e tests require an emulator (PR #86489)

[Mehdi Amini]

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@@ -13,6 +13,104 @@ set(MLIR_CMAKE_DIR
 # Passed to lit.site.cfg.py.in to set up the path where to find libraries.
 set(MLIR_LIB_DIR ${CMAKE_LIBRARY_OUTPUT_DIRECTORY})
 
+# Checks whether the specified hardware capability is supported by the host
+# Linux system. This is implemented by checking auxiliary vector feature
+# provided by the Linux kernel.
+#
+# check_hwcap(
+#   hwcap_spec
+#   output_var
+# )
+#
+# hwcap_spec - HWCAP value to check - these are defined in hwcap.h in the Linux
+#              kernel.
+#
+# output_var - Output variable to use to save the results (TRUE for supported,
+#              FALSE for not supported).
+#
+# EXAMPLES:
+#
+# check_hwcap("HWCAP2_SME" SME_EMULATOR_REQUIRED)
+#
+function(check_hwcap hwcap_spec output)
+    set(hwcap_test_src
+      [====[
+      #include <asm/hwcap.h>
+      #include <sys/auxv.h>
+
+      int main(void)
+      {
+          long hwcaps = getauxval(AT_<HWCAP_VEC>);
+          return (hwcaps & <HWCAP_SPEC>) != 0;
+      }
+      ]====]
+    )
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joker-eph wrote:

I thought you'd write some inline ASM performing a simple SVE operation and check that it does not crash, so that you wouldn't depend on any header.

I'm fine with this though.

https://github.com/llvm/llvm-project/pull/86489