[mlir][linalg] Add padding helper functions to PadTensorOp

[springerm]

Summary

Add helper functions to quickly check for zero low/high padding.

Depends On D103763

mlir/include/mlir/Dialect/Linalg/IR/LinalgOps.td

inline SmallVector<OpFoldResult> getMixedPadImpl(ArrayAttr staticAttrs,
       return res;
     }
     SmallVector<OpFoldResult> getMixedLowPad() {
       return getMixedPadImpl(static_low(), low());
     }
     SmallVector<OpFoldResult> getMixedHighPad() {
       return getMixedPadImpl(static_high(), high());
     }
+    // Return true if low padding is guaranteed to be 0.
+    bool hasZeroLowPad() {
+      return llvm::all_of(getMixedLowPad(), [](OpFoldResult ofr) {
+        return mlir::isEqualConstantInt(ofr, 0);
+      });
+    }
+    // Return true if high padding is guaranteed to be 0.
+    bool hasZeroHighPad() {
+      return llvm::all_of(getMixedHighPad(), [](OpFoldResult ofr) {
+        return mlir::isEqualConstantInt(ofr, 0);
+      });
+    }
   }];
 
   let builders = [
     // Build a PadTensorOp with mixed static and dynamic entries.
     OpBuilder<(ins "Value":$source, "ArrayRef<int64_t>":$staticLow,
       "ArrayRef<int64_t>":$staticHigh, "ValueRange":$low, "ValueRange":$high,
       CArg<"ArrayRef<NamedAttribute>", "{}">:$attrs)>,
     // Build a PadTensorOp with all dynamic entries.