[flang][cuda] Add interfaces for __ll2float_rX (#153694)

Author: clementval

flang/module/cudadevice.f90

@@ -681,6 +681,34 @@ attributes(device) real(8) function sinpi(x) bind(c,name='__nv_sinpi')
     end function
   end interface
 
+  interface __ll2float_rd
+    attributes(device) real function __ll2float_rd(i) bind(c, name='__nv_ll2float_rd')
+      !dir$ ignore_tkr (d) i
+      integer(8), value :: i
+    end function
+  end interface
+
+  interface __ll2float_rn
+    attributes(device) real function __ll2float_rn(i) bind(c, name='__nv_ll2float_rn')
+      !dir$ ignore_tkr (d) i
+      integer(8), value :: i
+    end function
+    end interface
+
+  interface __ll2float_ru
+    attributes(device) real function __ll2float_ru(i) bind(c, name='__nv_ll2float_ru')
+      !dir$ ignore_tkr (d) i
+      integer(8), value :: i
+    end function
+  end interface
+
+  interface __ll2float_rz
+    attributes(device) real function __ll2float_rz(i) bind(c, name='__nv_ll2float_rz')
+      !dir$ ignore_tkr (d) i
+      integer(8), value :: i
+    end function
+  end interface
+
   interface __ll2double_rd
     attributes(device) double precision function __ll2double_rd(i) bind(c, name='__nv_ll2double_rd')
       !dir$ ignore_tkr (d) i

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

@@ -161,3 +161,18 @@ end subroutine
 ! CHECK: %{{.*}} = fir.call @__nv_double2ull_rn(%{{.*}}) proc_attrs<bind_c> fastmath<contract> : (f64) -> i64
 ! CHECK: %{{.*}} = fir.call @__nv_double2ull_ru(%{{.*}}) proc_attrs<bind_c> fastmath<contract> : (f64) -> i64
 ! CHECK: %{{.*}} = fir.call @__nv_double2ull_rz(%{{.*}}) proc_attrs<bind_c> fastmath<contract> : (f64) -> i64
+
+attributes(global) subroutine test_ll2float_rX()
+  real :: res
+  integer(8) :: i
+  res = __ll2float_rd(i)
+  res = __ll2float_rn(i)
+  res = __ll2float_ru(i)
+  res = __ll2float_rz(i)
+end subroutine
+
+! CHECK-LABEL: _QPtest_ll2float_rx
+! CHECK: %{{.*}} = fir.call @__nv_ll2float_rd(%{{.*}}) proc_attrs<bind_c> fastmath<contract> : (i64) -> f32
+! 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