[clang] [llvm] [mlir] [MLIR][OpenMP] Add codegen for teams reductions (PR #133310)

[Sergio Afonso via llvm-commits]

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@@ -0,0 +1,71 @@
+// RUN: mlir-translate -mlir-to-llvmir -split-input-file %s | FileCheck %s
+
+// Only check the overall shape of the code and the presence of relevant
+// runtime calls. Actual IR checking is done at the OpenMPIRBuilder level.
+
+omp.private {type = private} @_QFsimple_teams_reductionEindex__private_i32 : i32
+omp.declare_reduction @add_reduction_i32 : i32 init {
+^bb0(%arg0: i32):
+  %0 = llvm.mlir.constant(0 : i32) : i32
+  omp.yield(%0 : i32)
+} combiner {
+^bb0(%arg0: i32, %arg1: i32):
+  %0 = llvm.add %arg0, %arg1 : i32
+  omp.yield(%0 : i32)
+}
+llvm.func @simple_teams_reduction_() attributes {fir.internal_name = "_QPsimple_teams_reduction", frame_pointer = #llvm.framePointerKind<all>, target_cpu = "x86-64"} {
+  %0 = llvm.mlir.constant(1 : i64) : i64
+  %1 = llvm.alloca %0 x i32 {bindc_name = "sum"} : (i64) -> !llvm.ptr
+  %2 = llvm.mlir.constant(1 : i64) : i64
+  %3 = llvm.alloca %2 x i32 {bindc_name = "index_"} : (i64) -> !llvm.ptr
+  %4 = llvm.mlir.constant(10000 : i32) : i32
+  %5 = llvm.mlir.constant(1 : i32) : i32
+  %6 = llvm.mlir.constant(0 : i32) : i32
+  %7 = llvm.mlir.constant(1 : i64) : i64
+  %8 = llvm.mlir.constant(1 : i64) : i64
+  llvm.store %6, %1 : i32, !llvm.ptr
+  omp.teams reduction(@add_reduction_i32 %1 -> %arg0 : !llvm.ptr) {
+    omp.distribute private(@_QFsimple_teams_reductionEindex__private_i32 %3 -> %arg1 : !llvm.ptr) {
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skatrak wrote:

This is a teams+distribute reduction, could you add a test for a teams-only reduction as well?

https://github.com/llvm/llvm-project/pull/133310