[FRONTEND] Mangle signed and unsigned integer types differently (#1340)

This is cherry-picked from #1305

If you call a `JITFunction` twice in the same kernel, first with `int32`
then with `uint32`, the second call will treat the unsigned value as
signed. This passes through MLIR without error because MLIR uses the
same types for both, but different operation calls will be generated so
you may silently get the wrong result.

python/test/unit/language/test_core.py

@@ -295,6 +295,43 @@ def test_floordiv(dtype_x, dtype_y, device='cuda'):
     _test_binary(dtype_x, dtype_y, expr, numpy_expr, device=device)
 
 
+def test_unsigned_name_mangling(device='cuda'):
+    # Test that uint32 and int32 are mangled differently by the compiler
+    SIZE = 128
+    # define the kernel / launch-grid
+
+    @triton.jit
+    def kernel(O1, O2, X, Y, SIZE: tl.constexpr):
+        off = tl.arange(0, SIZE)
+        x = tl.load(X + off)
+        y = tl.load(Y + off)
+        out1 = tl.abs(x)  # uint32 -> nop
+        out2 = tl.abs(-y)  # int32 -> should have an effect
+        tl.store(O1 + off, out1)
+        tl.store(O2 + off, out2)
+
+    dtype_x = 'uint32'
+    dtype_y = 'int32'
+    # inputs
+    rs = RandomState(17)
+    x = numpy_random(SIZE, dtype_str=dtype_x, rs=rs)
+    y = numpy_random(SIZE, dtype_str=dtype_y, rs=rs)
+    # reference result
+    expect = (np.abs(x), np.abs(-y))
+    # triton result
+    x_tri = to_triton(x, device=device, dst_type=dtype_x)
+    y_tri = to_triton(y, device=device, dst_type=dtype_y)
+    actual = tuple(
+        to_triton(np.empty_like(e), device=device)
+        for e in expect
+    )
+    kernel[(1, )](actual[0], actual[1], x_tri, y_tri, SIZE=SIZE, num_warps=4)
+
+    # Bitwise op, so expect exact equality
+    assert (expect[0] == to_numpy(actual[0])).all()
+    assert (expect[1] == to_numpy(actual[1])).all()
+
+
 # ---------------
 # test bitwise ops
 # ---------------

python/triton/compiler.py

@@ -57,7 +57,9 @@ def mangle_ty(ty):
     if ty.is_ptr():
         return 'P' + mangle_ty(ty.element_ty)
     if ty.is_int():
-        return 'i' + str(ty.int_bitwidth)
+        SIGNED = triton.language.dtype.SIGNEDNESS.SIGNED
+        prefix = 'i' if ty.int_signedness == SIGNED else 'u'
+        return prefix + str(ty.int_bitwidth)
     if ty.is_fp8():
         return 'fp8'
     if ty.is_fp16():