[libc] [llvm] [libc] Improve qsort (PR #120450)

[Michael Jones via llvm-commits]

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@@ -15,9 +15,13 @@
 #define LIBC_QSORT_QUICK_SORT 1
 #define LIBC_QSORT_HEAP_SORT 2
 
+#ifdef LIBC_OPTIMIZE_FOR_SIZE
+#define LIBC_QSORT_IMPL LIBC_QSORT_HEAP_SORT
+#else
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michaelrj-google wrote:

`config.json` is how we set up the compile flags for individual targets (the one I linked is the primary one but there are others in `/config/<TARGET>/<ARCH>/`. In future we'll likely have something similar to `LIBC_OPTIMIZE_FOR_SIZE` but in the build system so that we can have a cmake flag that sets lots of individual macros, while also allowing for fine tuning if necessary.

In short: I like the idea, but I don't think it fits into this patch. Perhaps in a followup?

https://github.com/llvm/llvm-project/pull/120450