Revert "GEP with a constant offset should have inbounds attribute."

This reverts commit 5415cbc.

Author: liusy58

mlir/include/mlir/Dialect/LLVMIR/LLVMOps.td

@@ -296,7 +296,7 @@ def LLVM_GEPOp : LLVM_Op<"getelementptr", [Pure,
   let skipDefaultBuilders = 1;
 
   let description = [{
-    This operation mirrors LLVM IR's 'getelementptr' operation that is used to
+    This operation mirrors LLVM IRs 'getelementptr' operation that is used to
     perform pointer arithmetic.
 
     Like in LLVM IR, it is possible to use both constants as well as SSA values
@@ -334,28 +334,16 @@ def LLVM_GEPOp : LLVM_Op<"getelementptr", [Pure,
     indices.reserve($rawConstantIndices.size());
     GEPIndicesAdaptor<decltype($dynamicIndices)>
         gepIndices(op.getRawConstantIndicesAttr(), $dynamicIndices);
-
-    for (const auto &valueOrAttr : gepIndices) {
-      if (llvm::isa<mlir::IntegerAttr>(valueOrAttr)) {
-        auto intAttr = valueOrAttr.get<mlir::IntegerAttr>();
-        indices.push_back(builder.getInt32(intAttr.getInt()));
-      } else {
-        indices.push_back(valueOrAttr.get<llvm::Value*>());
-      }
-    }
-
-    bool allIndicesConstant = true;
-    for(llvm::Value* value: indices) {
-      if(auto *C = dyn_cast<llvm::Constant>(value)) {
-        continue;
-      } else {
-        allIndicesConstant = false;
-        break;
-      }
+    for (PointerUnion<IntegerAttr, llvm::Value*> valueOrAttr : gepIndices) {
+      if (llvm::Value* value = ::llvm::dyn_cast<llvm::Value*>(valueOrAttr))
+        indices.push_back(value);
+      else
+        indices.push_back(
+            builder.getInt32(valueOrAttr.get<IntegerAttr>().getInt()));
     }
     Type baseElementType = op.getElemType();
     llvm::Type *elementType = moduleTranslation.convertType(baseElementType);
-    $res = builder.CreateGEP(elementType, $base, indices, "", $inbounds?true:allIndicesConstant);
+    $res = builder.CreateGEP(elementType, $base, indices, "", $inbounds);
   }];
   let assemblyFormat = [{
     (`inbounds` $inbounds^)?