[llvm] [SPIR-V] Prevent adding duplicate binding instructions for implicit binding (PR #161299)

[Lucie Choi via llvm-commits]

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@@ -112,11 +112,22 @@ uint32_t SPIRVLegalizeImplicitBinding::getAndReserveFirstUnusedBinding(
 }
 
 void SPIRVLegalizeImplicitBinding::replaceImplicitBindingCalls(Module &M) {
+  std::unordered_map<uint32_t, uint32_t> OrderIdToBinding;
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luciechoi wrote:

Right, thanks for pointing out, I replaced the map with two variables `lastOrderId` and `lastBindingNumber`. 

https://github.com/llvm/llvm-project/pull/161299