diff --git a/llvm/include/llvm/ADT/APInt.h b/llvm/include/llvm/ADT/APInt.h
index 63a138527b32e..953b2a27b7152 100644
--- a/llvm/include/llvm/ADT/APInt.h
+++ b/llvm/include/llvm/ADT/APInt.h
@@ -109,7 +109,7 @@ class [[nodiscard]] APInt {
   /// \param implicitTrunc allow implicit truncation of non-zero/sign bits of
   ///                      val beyond the range of numBits
   APInt(unsigned numBits, uint64_t val, bool isSigned = false,
-        bool implicitTrunc = true)
+        bool implicitTrunc = false)
       : BitWidth(numBits) {
     if (!implicitTrunc) {
       if (isSigned) {
diff --git a/mlir/lib/Dialect/PDL/IR/Builtins.cpp b/mlir/lib/Dialect/PDL/IR/Builtins.cpp
index 770a390a3fe5f..9e4efbf7e71c0 100644
--- a/mlir/lib/Dialect/PDL/IR/Builtins.cpp
+++ b/mlir/lib/Dialect/PDL/IR/Builtins.cpp
@@ -63,7 +63,8 @@ LogicalResult static unaryOp(PatternRewriter &rewriter, PDLResultList &results,
               ? std::pow(2, operandIntAttr.getValue().getZExtValue())
               : std::pow(2, operandIntAttr.getValue().getSExtValue());
 
-      APInt resultInt(bitWidth, resultVal, integerType.isSigned());
+      APInt resultInt(bitWidth, resultVal, integerType.isSigned(),
+                      /*implicitTrunc*/ true);
 
       bool isOverflow = integerType.isSigned()
                             ? resultInt.slt(operandIntAttr.getValue())
diff --git a/mlir/lib/Dialect/Tosa/IR/TosaCanonicalizations.cpp b/mlir/lib/Dialect/Tosa/IR/TosaCanonicalizations.cpp
index 5e5c39507057a..732f794206cd8 100644
--- a/mlir/lib/Dialect/Tosa/IR/TosaCanonicalizations.cpp
+++ b/mlir/lib/Dialect/Tosa/IR/TosaCanonicalizations.cpp
@@ -155,18 +155,43 @@ struct SelectToClampOptimization : public OpRewritePattern<tosa::SelectOp> {
       return rewriter.notifyMatchFailure(
           op, "RHS of predicate GreaterEqualOp is not a constant");
     }
+
     auto isCompatibleSplat = [](DenseElementsAttr a,
                                 DenseElementsAttr b) -> bool {
       if (!a.isSplat() || !b.isSplat()) {
         return false;
       }
-      if (llvm::isa<IntegerType>(a.getElementType())) {
-        return a.getSplatValue<APInt>() == b.getSplatValue<APInt>();
+
+      auto aAsIntegerType = dyn_cast<IntegerType>(a.getElementType());
+      auto bAsIntegerType = dyn_cast<IntegerType>(b.getElementType());
+      if (aAsIntegerType && bAsIntegerType) {
+        if (aAsIntegerType.getSignedness() != bAsIntegerType.getSignedness()) {
+          return false;
+        }
+
+        auto aAsAPInt = a.getSplatValue<APInt>();
+        auto bAsAPInt = b.getSplatValue<APInt>();
+
+        const size_t aBitWidth = aAsAPInt.getBitWidth();
+        const size_t bBitWidth = bAsAPInt.getBitWidth();
+
+        if (aBitWidth >= bBitWidth) {
+          return aAsAPInt == (bAsIntegerType.isUnsigned()
+                                  ? bAsAPInt.zext(aBitWidth)
+                                  : bAsAPInt.sext(aBitWidth));
+        }
+        return (aAsIntegerType.isUnsigned()
+                    ? aAsAPInt.zext(bBitWidth)
+                    : aAsAPInt.sext(bBitWidth)) == bAsAPInt;
       }
-      if (llvm::isa<FloatType>(a.getElementType())) {
-        return a.getSplatValue<APFloat>() == b.getSplatValue<APFloat>();
+
+      auto aAsFloatType = dyn_cast<FloatType>(a.getElementType());
+      auto bAsFloatType = dyn_cast<FloatType>(b.getElementType());
+      if (!aAsFloatType || aAsFloatType != bAsFloatType) {
+        return false;
       }
-      return false; // Only int and float types are supported
+
+      return a.getSplatValue<APFloat>() == b.getSplatValue<APFloat>();
     };
 
     auto onFalse = op.getOnFalse();
@@ -237,10 +262,25 @@ struct SelectToClampOptimization : public OpRewritePattern<tosa::SelectOp> {
         clampFloatMax = rewriter.getFloatAttr(inputElementType, splatValue);
       }
     }
+
+    Value input = geq.getInput1();
+
+    // In case they do not have same bit width, insert a cast to still be able
+    // to do this canonicalization
+    const size_t geqBitWidth =
+        geq.getInput1().getType().getElementTypeBitWidth();
+    const size_t selectBitWidth = op.getType().getElementTypeBitWidth();
+    if (geqBitWidth != selectBitWidth) {
+      input = rewriter.create<tosa::CastOp>(
+          op->getLoc(),
+          geq.getInput1().getType().clone(op.getType().getElementType()),
+          input);
+    }
+
     rewriter.replaceOpWithNewOp<tosa::ClampOp>(
-        op, op.getType(), geq.getInput1(),
-        rewriter.getI64IntegerAttr(clampIntMin),
+        op, op.getType(), input, rewriter.getI64IntegerAttr(clampIntMin),
         rewriter.getI64IntegerAttr(clampIntMax), clampFloatMin, clampFloatMax);
+
     return success();
   }
 };
diff --git a/mlir/lib/Dialect/Tosa/Transforms/TosaFolders.cpp b/mlir/lib/Dialect/Tosa/Transforms/TosaFolders.cpp
index 63594d83ccc11..ea6f295ff2feb 100644
--- a/mlir/lib/Dialect/Tosa/Transforms/TosaFolders.cpp
+++ b/mlir/lib/Dialect/Tosa/Transforms/TosaFolders.cpp
@@ -1540,9 +1540,11 @@ struct TosaFoldConstantMatMul
 
     // Convert int64_t to the correct output type.
     std::vector<APInt> apintValues;
-    llvm::transform(values, std::back_inserter(apintValues),
-                    [&](const int64_t &val) {
-                      APInt apIntVal(baseType.getIntOrFloatBitWidth(), val);
+    llvm::transform(
+        values, std::back_inserter(apintValues), [&](const int64_t &val) {
+          APInt apIntVal(baseType.getIntOrFloatBitWidth(), val,
+                         /*isSigned=*/true); // tosa-mlir uses signless
+                                             // instead of signed
                       return apIntVal;
                     });
     return DenseElementsAttr::get(outputType, apintValues);
diff --git a/mlir/test/Dialect/Tosa/canonicalize.mlir b/mlir/test/Dialect/Tosa/canonicalize.mlir
index 4e10833a775c3..b341a774442ba 100644
--- a/mlir/test/Dialect/Tosa/canonicalize.mlir
+++ b/mlir/test/Dialect/Tosa/canonicalize.mlir
@@ -1147,3 +1147,59 @@ func.func @canonicalize_select_lrelu_zero_pattern(%arg0: tensor<13x21x3xf32>) ->
   return %3  :  tensor<13x21x3xf32>
 }
 
+// -----
+
+// CHECK-LABEL: @canonicalize_select_to_clamp_i64_and_i8_pat1
+func.func @canonicalize_select_to_clamp_i64_and_i8_pat1(%arg0: tensor<13x21x3xi64>, %arg1: tensor<13x21x3xi8>) -> tensor<13x21x3xi8> {
+// CHECK:           %[[VAL_1:.*]] = tosa.cast %arg{{.*}} : (tensor<13x21x3xi64>) -> tensor<13x21x3xi8>
+// CHECK:           %[[VAL_2:.*]] = tosa.clamp %[[VAL_1]] {max_fp = 0x7F800000 : f32, max_int = 9223372036854775807 : i64, min_fp = 0xFF800000 : f32, min_int = 42 : i64} : (tensor<13x21x3xi8>) -> tensor<13x21x3xi8>
+// CHECK:           return %[[VAL_2]] : tensor<13x21x3xi8>
+  %0 =  "tosa.const"() <{value = dense<42> : tensor<13x21x3xi64>}>: () -> tensor<13x21x3xi64>
+  %1 =  "tosa.const"() <{value = dense<42> : tensor<13x21x3xi8>}>: () -> tensor<13x21x3xi8>
+  %2 = tosa.greater_equal %arg0, %0: (tensor<13x21x3xi64>, tensor<13x21x3xi64>) -> tensor<13x21x3xi1>
+  %3 = tosa.select %2, %arg1, %1: ( tensor<13x21x3xi1>, tensor<13x21x3xi8>, tensor<13x21x3xi8>) -> tensor<13x21x3xi8>
+  return %3  :  tensor<13x21x3xi8>
+}
+
+// -----
+
+// CHECK-LABEL: @canonicalize_select_to_clamp_i64_and_i8_pat2
+func.func @canonicalize_select_to_clamp_i64_and_i8_pat2(%arg0: tensor<13x21x3xi64>, %arg1: tensor<13x21x3xi8>) -> tensor<13x21x3xi8> {
+// CHECK:           %[[VAL_1:.*]] = tosa.cast %arg{{.*}} : (tensor<13x21x3xi64>) -> tensor<13x21x3xi8>
+// CHECK:           %[[VAL_2:.*]] = tosa.clamp %[[VAL_1]] {max_fp = 0x7F800000 : f32, max_int = -42 : i64, min_fp = 0xFF800000 : f32, min_int = -9223372036854775808 : i64} : (tensor<13x21x3xi8>) -> tensor<13x21x3xi8>
+// CHECK:           return %[[VAL_2]] : tensor<13x21x3xi8>
+  %0 =  "tosa.const"() <{value = dense<-42> : tensor<13x21x3xi64>}>: () -> tensor<13x21x3xi64>
+  %1 =  "tosa.const"() <{value = dense<-42> : tensor<13x21x3xi8>}>: () -> tensor<13x21x3xi8>
+  %2 = tosa.greater_equal %arg0, %0: (tensor<13x21x3xi64>, tensor<13x21x3xi64>) -> tensor<13x21x3xi1>
+  %3 = tosa.select %2, %1, %arg1 : ( tensor<13x21x3xi1>, tensor<13x21x3xi8>, tensor<13x21x3xi8>) -> tensor<13x21x3xi8>
+  return %3  :  tensor<13x21x3xi8>
+}
+
+// -----
+
+// CHECK-LABEL: @canonicalize_select_to_clamp_i8_and_i64_pat1
+func.func @canonicalize_select_to_clamp_i8_and_i64_pat1(%arg0: tensor<13x21x3xi8>, %arg1: tensor<13x21x3xi64>) -> tensor<13x21x3xi64> {
+// CHECK:           %[[VAL_1:.*]] = tosa.cast %arg{{.*}} : (tensor<13x21x3xi8>) -> tensor<13x21x3xi64>
+// CHECK:           %[[VAL_2:.*]] = tosa.clamp %[[VAL_1]] {max_fp = 0x7F800000 : f32, max_int = 9223372036854775807 : i64, min_fp = 0xFF800000 : f32, min_int = 42 : i64} : (tensor<13x21x3xi64>) -> tensor<13x21x3xi64>
+// CHECK:           return %[[VAL_2]] : tensor<13x21x3xi64>
+  %0 =  "tosa.const"() <{value = dense<42> : tensor<13x21x3xi8>}>: () -> tensor<13x21x3xi8>
+  %1 =  "tosa.const"() <{value = dense<42> : tensor<13x21x3xi64>}>: () -> tensor<13x21x3xi64>
+  %2 = tosa.greater_equal %arg0, %0: (tensor<13x21x3xi8>, tensor<13x21x3xi8>) -> tensor<13x21x3xi1>
+  %3 = tosa.select %2, %arg1, %1: ( tensor<13x21x3xi1>, tensor<13x21x3xi64>, tensor<13x21x3xi64>) -> tensor<13x21x3xi64>
+  return %3  :  tensor<13x21x3xi64>
+}
+
+// -----
+
+// CHECK-LABEL: @canonicalize_select_to_clamp_i8_and_i64_pat2
+func.func @canonicalize_select_to_clamp_i8_and_i64_pat2(%arg0: tensor<13x21x3xi8>, %arg1: tensor<13x21x3xi64>) -> tensor<13x21x3xi64> {
+// CHECK:           %[[VAL_1:.*]] = tosa.cast %arg{{.*}} : (tensor<13x21x3xi8>) -> tensor<13x21x3xi64>
+// CHECK:           %[[VAL_2:.*]] = tosa.clamp %[[VAL_1]] {max_fp = 0x7F800000 : f32, max_int = -42 : i64, min_fp = 0xFF800000 : f32, min_int = -9223372036854775808 : i64} : (tensor<13x21x3xi64>) -> tensor<13x21x3xi64>
+// CHECK:           return %[[VAL_2]] : tensor<13x21x3xi64>
+  %0 =  "tosa.const"() <{value = dense<-42> : tensor<13x21x3xi8>}>: () -> tensor<13x21x3xi8>
+  %1 =  "tosa.const"() <{value = dense<-42> : tensor<13x21x3xi64>}>: () -> tensor<13x21x3xi64>
+  %2 = tosa.greater_equal %arg0, %0: (tensor<13x21x3xi8>, tensor<13x21x3xi8>) -> tensor<13x21x3xi1>
+  %3 = tosa.select %2, %1, %arg1: ( tensor<13x21x3xi1>, tensor<13x21x3xi64>, tensor<13x21x3xi64>) -> tensor<13x21x3xi64>
+  return %3  :  tensor<13x21x3xi64>
+}
+