[mlir] Add debug messages for failures of isValidIntOrFloat

I have run into assertion failures quite often when calling this method
via `DenseElementsAttr::get`, and I think this would help, at the very
least, by printing out the bit width size mismatches, rather than a
plain assertion failure. I included all the other cases in the method
for completeness

Author: j2kun

mlir/lib/IR/BuiltinAttributes.cpp

@@ -20,9 +20,12 @@
 #include "llvm/ADT/APSInt.h"
 #include "llvm/ADT/Sequence.h"
 #include "llvm/ADT/TypeSwitch.h"
+#include "llvm/Support/Debug.h"
 #include "llvm/Support/Endian.h"
 #include <optional>
 
+#define DEBUG_TYPE "builtinattributes"
+
 using namespace mlir;
 using namespace mlir::detail;
 
@@ -1098,24 +1101,44 @@ bool DenseElementsAttr::isValidRawBuffer(ShapedType type,
 static bool isValidIntOrFloat(Type type, int64_t dataEltSize, bool isInt,
                               bool isSigned) {
   // Make sure that the data element size is the same as the type element width.
-  if (getDenseElementBitWidth(type) !=
-      static_cast<size_t>(dataEltSize * CHAR_BIT))
+  auto denseEltBitWidth = getDenseElementBitWidth(type);
+  auto dataSize = static_cast<size_t>(dataEltSize * CHAR_BIT);
+  if (denseEltBitWidth != dataSize) {
+    LLVM_DEBUG(llvm::dbgs() << "expected dense element bit width "
+                            << denseEltBitWidth << " to match data size "
+                            << dataSize << " for type " << type << "\n");
     return false;
+  }
 
   // Check that the element type is either float or integer or index.
-  if (!isInt)
-    return llvm::isa<FloatType>(type);
+  if (!isInt) {
+    bool valid = llvm::isa<FloatType>(type);
+    if (!valid)
+      LLVM_DEBUG(llvm::dbgs()
+                 << "expected float type when isInt is false, but found "
+                 << type << "\n");
+    return valid;
+  }
   if (type.isIndex())
     return true;
 
   auto intType = llvm::dyn_cast<IntegerType>(type);
-  if (!intType)
+  if (!intType) {
+    LLVM_DEBUG(llvm::dbgs()
+               << "expected integer type when isInt is true, but found " << type
+               << "\n");
     return false;
+  }
 
   // Make sure signedness semantics is consistent.
   if (intType.isSignless())
     return true;
-  return intType.isSigned() ? isSigned : !isSigned;
+
+  bool valid = intType.isSigned() == isSigned;
+  if (!valid)
+    LLVM_DEBUG(llvm::dbgs() << "expected signedness " << isSigned
+                            << " to match type " << type << "\n");
+  return valid;
 }
 
 /// Defaults down the subclass implementation.
@@ -1247,12 +1270,14 @@ DenseElementsAttr DenseElementsAttr::bitcast(Type newElType) {
 DenseElementsAttr
 DenseElementsAttr::mapValues(Type newElementType,
                              function_ref<APInt(const APInt &)> mapping) const {
-  return llvm::cast<DenseIntElementsAttr>(*this).mapValues(newElementType, mapping);
+  return llvm::cast<DenseIntElementsAttr>(*this).mapValues(newElementType,
+                                                           mapping);
 }
 
 DenseElementsAttr DenseElementsAttr::mapValues(
     Type newElementType, function_ref<APInt(const APFloat &)> mapping) const {
-  return llvm::cast<DenseFPElementsAttr>(*this).mapValues(newElementType, mapping);
+  return llvm::cast<DenseFPElementsAttr>(*this).mapValues(newElementType,
+                                                          mapping);
 }
 
 ShapedType DenseElementsAttr::getType() const {
@@ -1331,8 +1356,9 @@ DenseElementsAttr DenseIntOrFPElementsAttr::getRawComplex(ShapedType type,
                                                           bool isInt,
                                                           bool isSigned) {
   assert(::isValidIntOrFloat(
-      llvm::cast<ComplexType>(type.getElementType()).getElementType(),
-      dataEltSize / 2, isInt, isSigned));
+             llvm::cast<ComplexType>(type.getElementType()).getElementType(),
+             dataEltSize / 2, isInt, isSigned) &&
+         "Try re-running with -debug-only=builtinattributes");
 
   int64_t numElements = data.size() / dataEltSize;
   (void)numElements;
@@ -1347,8 +1373,9 @@ DenseElementsAttr
 DenseIntOrFPElementsAttr::getRawIntOrFloat(ShapedType type, ArrayRef<char> data,
                                            int64_t dataEltSize, bool isInt,
                                            bool isSigned) {
-  assert(
-      ::isValidIntOrFloat(type.getElementType(), dataEltSize, isInt, isSigned));
+  assert(::isValidIntOrFloat(type.getElementType(), dataEltSize, isInt,
+                             isSigned) &&
+         "Try re-running with -debug-only=builtinattributes");
 
   int64_t numElements = data.size() / dataEltSize;
   assert(numElements == 1 || numElements == type.getNumElements());