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

[Steven Perron via llvm-commits]

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@@ -92,6 +92,32 @@ void SPIRVLegalizeImplicitBinding::collectBindingInfo(Module &M) {
             cast<ConstantInt>(B->getArgOperand(OrderIdArgIdx))->getZExtValue();
         return OrderA < OrderB;
       });
+
+  // Check that the order Id is unique per resource.
+  for (uint32_t i = 1; i < ImplicitBindingCalls.size(); ++i) {
+    const uint32_t OrderIdArgIdx = 0;
+    const uint32_t DescSetArgIdx = 1;
+    const uint32_t OrderA =
+        cast<ConstantInt>(
+            ImplicitBindingCalls[i - 1]->getArgOperand(OrderIdArgIdx))
+            ->getZExtValue();
+    const uint32_t OrderB =
+        cast<ConstantInt>(ImplicitBindingCalls[i]->getArgOperand(OrderIdArgIdx))
+            ->getZExtValue();
+    if (OrderA == OrderB) {
+      const uint32_t DescSetA =
+          cast<ConstantInt>(
+              ImplicitBindingCalls[i - 1]->getArgOperand(DescSetArgIdx))
+              ->getZExtValue();
+      const uint32_t DescSetB =
+          cast<ConstantInt>(
+              ImplicitBindingCalls[i]->getArgOperand(DescSetArgIdx))
+              ->getZExtValue();
+      assert(DescSetA == DescSetB &&
+             "If two implicit binding calls have the same order ID, they must "
+             "also have the same descriptor set.");
+    }
+  }
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s-perron wrote:

I think all of this should be moved out into it own function. `verifyUniqueOrderIdPerResource(ImplicitBindingCalls)`.

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