[llvm] [clang] [clang-tools-extra] [X86] Use plain load/store instead of cmpxchg16b for atomics with AVX (PR #74275)

[James Y Knight via cfe-commits]

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@@ -30115,12 +30126,16 @@ X86TargetLowering::shouldExpandAtomicLoadInIR(LoadInst *LI) const {
   // If this a 64 bit atomic load on a 32-bit target and SSE2 is enabled, we
   // can use movq to do the load. If we have X87 we can load into an 80-bit
   // X87 register and store it to a stack temporary.
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jyknight wrote:

Done.

https://github.com/llvm/llvm-project/pull/74275