[flang][cuda] Add interfaces for __int2float_rX (#153708)

Author: clementval

flang/module/cudadevice.f90

@@ -674,6 +674,34 @@ attributes(device) real(8) function sinpi(x) bind(c,name='__nv_sinpi')
     end function
   end interface
 
+  interface __int2float_rd
+    attributes(device) real function __int2float_rd(i) bind(c, name='__nv_int2float_rd')
+      !dir$ ignore_tkr (d) i
+      integer, value :: i
+    end function
+  end interface
+
+  interface __int2float_rn
+    attributes(device) real function __int2float_rn(i) bind(c, name='__nv_int2float_rn')
+      !dir$ ignore_tkr (d) i
+      integer, value :: i
+    end function
+  end interface
+
+  interface __int2float_ru
+    attributes(device) real function __int2float_ru(i) bind(c, name='__nv_int2float_ru')
+      !dir$ ignore_tkr (d) i
+      integer, value :: i
+    end function
+  end interface
+
+  interface __int2float_rz
+    attributes(device) real function __int2float_rz(i) bind(c, name='__nv_int2float_rz')
+      !dir$ ignore_tkr (d) i
+      integer, value :: i
+    end function
+  end interface
+
   interface __int2double_rn
     attributes(device) double precision function __int2double_rn(i) bind(c)
       !dir$ ignore_tkr (d) i

flang/test/Lower/CUDA/cuda-libdevice.cuf

@@ -199,6 +199,22 @@ end subroutine
 ! CHECK: %{{.*}} = fir.call @__nv_ll2float_rn(%{{.*}}) proc_attrs<bind_c> fastmath<contract> : (i64) -> f32
 ! CHECK: %{{.*}} = fir.call @__nv_ll2float_ru(%{{.*}}) proc_attrs<bind_c> fastmath<contract> : (i64) -> f32
 ! CHECK: %{{.*}} = fir.call @__nv_ll2float_rz(%{{.*}}) proc_attrs<bind_c> fastmath<contract> : (i64) -> f32
+
+attributes(global) subroutine test_int2float_rX()
+  real :: res
+  integer :: i
+  res = __int2float_rd(i)
+  res = __int2float_rn(i)
+  res = __int2float_ru(i)
+  res = __int2float_rz(i)
+end subroutine
+
+! CHECK-LABEL: _QPtest_int2float_rx
+! CHECK: %{{.*}} = fir.call @__nv_int2float_rd(%{{.*}}) proc_attrs<bind_c> fastmath<contract> : (i32) -> f32
+! CHECK: %{{.*}} = fir.call @__nv_int2float_rn(%{{.*}}) proc_attrs<bind_c> fastmath<contract> : (i32) -> f32
+! CHECK: %{{.*}} = fir.call @__nv_int2float_ru(%{{.*}}) proc_attrs<bind_c> fastmath<contract> : (i32) -> f32
+! CHECK: %{{.*}} = fir.call @__nv_int2float_rz(%{{.*}}) proc_attrs<bind_c> fastmath<contract> : (i32) -> f32
+
 attributes(global) subroutine test_float2int_rX()
   integer :: res
   real :: r