[llvm] [RISCV] Loosen the requirement of shadow stack codegen to Zimop (PR #152251)

[Ming-Yi Lai via llvm-commits]

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@@ -62,6 +62,21 @@ defm SSAMOSWAP_W  : AMO_rr_aq_rl<0b01001, 0b010, "ssamoswap.w">;
 let Predicates = [HasStdExtZicfiss, IsRV64] in
 defm SSAMOSWAP_D  : AMO_rr_aq_rl<0b01001, 0b011, "ssamoswap.d">;
 
+let Predicates = [HasStdExtZimop] in {
+let hasSideEffects = 0, mayLoad = 0, mayStore = 1 in
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mylai-mtk wrote:

Yeah I think you're right. We should separate the extensions cleanly, so without Zicfiss, no SSP should be referenced.

https://github.com/llvm/llvm-project/pull/152251