[flang-commits] [flang] [Flang] Minloc elemental intrinsic lowering (PR #74828)

[Tom Eccles via flang-commits]

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@@ -0,0 +1,327 @@
+// RUN: fir-opt %s -opt-bufferization | FileCheck %s
+
+func.func @_QPtest(%arg0: !fir.box<!fir.array<?xi32>> {fir.bindc_name = "array"}, %arg1: !fir.ref<i32> {fir.bindc_name = "val"}, %arg2: !fir.box<!fir.array<?xi32>> {fir.bindc_name = "m"}) {
+  %c0 = arith.constant 0 : index
+  %0:2 = hlfir.declare %arg0 {uniq_name = "_QFtestEarray"} : (!fir.box<!fir.array<?xi32>>) -> (!fir.box<!fir.array<?xi32>>, !fir.box<!fir.array<?xi32>>)
+  %1:2 = hlfir.declare %arg2 {uniq_name = "_QFtestEm"} : (!fir.box<!fir.array<?xi32>>) -> (!fir.box<!fir.array<?xi32>>, !fir.box<!fir.array<?xi32>>)
+  %2:2 = hlfir.declare %arg1 {uniq_name = "_QFtestEval"} : (!fir.ref<i32>) -> (!fir.ref<i32>, !fir.ref<i32>)
+  %3 = fir.load %2#0 : !fir.ref<i32>
+  %4:3 = fir.box_dims %0#0, %c0 : (!fir.box<!fir.array<?xi32>>, index) -> (index, index, index)
+  %5 = fir.shape %4#1 : (index) -> !fir.shape<1>
+  %6 = hlfir.elemental %5 unordered : (!fir.shape<1>) -> !hlfir.expr<?x!fir.logical<4>> {
+  ^bb0(%arg3: index):
+    %8 = hlfir.designate %0#0 (%arg3)  : (!fir.box<!fir.array<?xi32>>, index) -> !fir.ref<i32>
+    %9 = fir.load %8 : !fir.ref<i32>
+    %10 = arith.cmpi sge, %9, %3 : i32
+    %11 = fir.convert %10 : (i1) -> !fir.logical<4>
+    hlfir.yield_element %11 : !fir.logical<4>
+  }
+  %7 = hlfir.minloc %0#0 mask %6 {fastmath = #arith.fastmath<contract>} : (!fir.box<!fir.array<?xi32>>, !hlfir.expr<?x!fir.logical<4>>) -> !hlfir.expr<1xi32>
+  hlfir.assign %7 to %1#0 : !hlfir.expr<1xi32>, !fir.box<!fir.array<?xi32>>
+  hlfir.destroy %7 : !hlfir.expr<1xi32>
+  hlfir.destroy %6 : !hlfir.expr<?x!fir.logical<4>>
+  return
+}
+// CHECK-LABEL: func.func @_QPtest(%arg0: !fir.box<!fir.array<?xi32>> {fir.bindc_name = "array"}, %arg1: !fir.ref<i32> {fir.bindc_name = "val"}, %arg2: !fir.box<!fir.array<?xi32>> {fir.bindc_name = "m"}) {
+// CHECK-NEXT:    %c1 = arith.constant 1 : index
+// CHECK-NEXT:    %c2147483647_i32 = arith.constant 2147483647 : i32
+// CHECK-NEXT:    %c1_i32 = arith.constant 1 : i32
+// CHECK-NEXT:    %c0_i32 = arith.constant 0 : i32
+// CHECK-NEXT:    %c0 = arith.constant 0 : index
+// CHECK-NEXT:    %0 = fir.alloca i32
+// CHECK-NEXT:    %1:2 = hlfir.declare %arg0 {uniq_name = "_QFtestEarray"} : (!fir.box<!fir.array<?xi32>>) -> (!fir.box<!fir.array<?xi32>>, !fir.box<!fir.array<?xi32>>)
+// CHECK-NEXT:    %2:2 = hlfir.declare %arg2 {uniq_name = "_QFtestEm"} : (!fir.box<!fir.array<?xi32>>) -> (!fir.box<!fir.array<?xi32>>, !fir.box<!fir.array<?xi32>>)
+// CHECK-NEXT:    %3:2 = hlfir.declare %arg1 {uniq_name = "_QFtestEval"} : (!fir.ref<i32>) -> (!fir.ref<i32>, !fir.ref<i32>)
+// CHECK-NEXT:    %4 = fir.load %3#0 : !fir.ref<i32>
+// CHECK-NEXT:    %5:3 = fir.box_dims %1#0, %c0 : (!fir.box<!fir.array<?xi32>>, index) -> (index, index, index)
+// CHECK-NEXT:    %6 = fir.shape %5#1 : (index) -> !fir.shape<1>
+// CHECK-NEXT:    %7 = hlfir.elemental %6 unordered : (!fir.shape<1>) -> !hlfir.expr<?x!fir.logical<4>> {
+// CHECK-NEXT:    ^bb0(%arg3: index):
+// CHECK-NEXT:      %14 = hlfir.designate %1#0 (%arg3)  : (!fir.box<!fir.array<?xi32>>, index) -> !fir.ref<i32>
+// CHECK-NEXT:      %15 = fir.load %14 : !fir.ref<i32>
+// CHECK-NEXT:      %16 = arith.cmpi sge, %15, %4 : i32
+// CHECK-NEXT:      %17 = fir.convert %16 : (i1) -> !fir.logical<4>
+// CHECK-NEXT:      hlfir.yield_element %17 : !fir.logical<4>
+// CHECK-NEXT:    }
----------------
tblah wrote:

After inlining the elemental, it is now unused.

Ideally we should be able to eliminate the dead code, but off the top of my head I don't think we can do this yet in flang (I guess LLVM might be able to do it).

Please could you get rid of the elemental and its hlfir.destroy operation, if the destroy is the only use other than for the minloc.

https://github.com/llvm/llvm-project/pull/74828