[clang] [llvm] [RISCV] Add a command line option to disable register overlap for vector indexed load. (PR #224739)

[Pengcheng Wang via llvm-commits]

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@@ -5855,6 +5855,10 @@ def mzilsd_word_align : Flag<["-"], "mzilsd-word-align">, Group<m_Group>,
   HelpText<"Allow Zilsd/Zclsd memory accesses to be 4-byte aligned (RISC-V only)">;
 def mzilsd_strict_align : Flag<["-"], "mzilsd-strict-align">, Group<m_Group>,
   HelpText<"Force all Zilsd/Zclsd memory accesses to be 8-byte aligned (RISC-V only)">;
+def mvector_index_load_overlap : Flag<["-"], "mvector-index-load-overlap">, Group<m_Group>,
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wangpc-pp wrote:

We can specify it via `-Xclang -target-feature -Xclang +XXX` in Clang, but if we want to sync up the behavior with GCC, we need to go through toolchain conventions?

https://github.com/llvm/llvm-project/pull/224739