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JUNE 15, 2026
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Test Now Requires AVX-512 at Runtime, Not Just Compile Time

Updates a test case to require AVX512F support at runtime, ensuring the code behaves correctly when the feature is actually used.

A test case (vect-early-break-no-epilog_11.c) was modified to require AVX512F support at runtime (avx512f_runtime) instead of only at compile time (avx512f_hw). This ensures that the test is only run on systems that actually have AVX-512 support available during execution, preventing false positives when cross-compiling or testing on systems without the necessary hardware.

In Details

The change modifies a dg-require-effective-target directive in gcc.dg/vect/vect-early-break-no-epilog_11.c from avx512f_hw to avx512f_runtime. This directive controls whether the test is executed based on target features. The _hw suffix checks for hardware support at compile time, while _runtime checks for it at runtime. This distinction is important for LTO builds.

For Context

This commit refines how GCC tests its ability to generate code for AVX-512, a set of advanced instructions for x86 processors that can significantly speed up certain types of computations. The change ensures that the test is only run if the AVX-512 instructions are actually available on the machine where the compiled program is executed. This avoids issues where the code might compile correctly but fail at runtime due to missing hardware support.

Filed Under: avx512testsuitevectorization