[clang] [Clang][RISCV] Allow three SiFive CLIC interrupt arguments (PR #216159)

[Sam Elliott via cfe-commits]

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@@ -16,6 +16,11 @@ void foo_nest_interrupt(void) {}
 __attribute__((interrupt("qci-nest", "qci-nest")))
 void foo_nest_nest_interrupt(void) {}
 
+// CHECK-LABEL: @foo_nest_nest_nest_interrupt() #0
+// CHECK: ret void
+__attribute__((interrupt("qci-nest", "qci-nest", "qci-nest")))
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lenary wrote:

A follow-up commit might want to prevent duplicate attribute kinds in this list, but I don't think it would be a correctness issue once these are translated for the backend.

https://github.com/llvm/llvm-project/pull/216159