[llvm] AArch64/ARM/PPC/X86: Add some atomic tests (PR #92933)

[Chen Zheng via llvm-commits]

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@@ -462,3 +462,212 @@ define i64 @and_i64_release(ptr %mem, i64 %operand) {
   %val = atomicrmw and ptr %mem, i64 %operand release
   ret i64 %val
 }
+
+define half @load_atomic_f16__seq_cst(ptr %ptr) {
+; PPC32-LABEL: load_atomic_f16__seq_cst:
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chenzheng1030 wrote:

@bzEq Hi, would you please help to check these atomic cases on PPC? Thank you!

https://github.com/llvm/llvm-project/pull/92933