[Mlir-commits] [mlir] [mlir][OpenMP] don't add compiler-generated barrier in single threaded code (PR #174105)

[Tom Eccles]

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@@ -0,0 +1,43 @@
+// RUN: mlir-translate -mlir-to-llvmir %s | FileCheck %s
+
+// tests that no privatization barrier is added for operations inside of SINGLE
+
+omp.private {type = private} @_QFwsloop_privateEi_private_ref_i32 : i32
+
+llvm.func @foo_free(!llvm.ptr)
+
+omp.private {type = firstprivate} @_QFwsloop_privateEc_firstprivate_ref_c8 : !llvm.array<1 x i8> copy {
+^bb0(%arg0: !llvm.ptr, %arg1: !llvm.ptr):
+  %0 = llvm.load %arg0 : !llvm.ptr -> !llvm.array<1 x i8>
+  llvm.store %0, %arg1 : !llvm.array<1 x i8>, !llvm.ptr
+  omp.yield(%arg1 : !llvm.ptr)
+} dealloc {
+^bb0(%arg0: !llvm.ptr):
+  llvm.call @foo_free(%arg0) : (!llvm.ptr) -> ()
+  omp.yield
+}
+
+llvm.func @wsloop_private_(%arg0: !llvm.ptr {fir.bindc_name = "y"}) attributes {fir.internal_name = "_QPwsloop_private", frame_pointer = #llvm.framePointerKind<all>, target_cpu = "x86-64"} {
+  %0 = llvm.mlir.constant(1 : i64) : i64
+  %1 = llvm.alloca %0 x f32 {bindc_name = "x"} : (i64) -> !llvm.ptr
+  %3 = llvm.alloca %0 x i32 {bindc_name = "i"} : (i64) -> !llvm.ptr
+  %5 = llvm.alloca %0 x !llvm.array<1 x i8> {bindc_name = "c"} : (i64) -> !llvm.ptr
+  %6 = llvm.mlir.constant(1 : i32) : i32
+  %7 = llvm.mlir.constant(10 : i32) : i32
+  %8 = llvm.mlir.constant(0 : i32) : i32
+  omp.parallel {
+    omp.single {
+      omp.wsloop private(@_QFwsloop_privateEc_firstprivate_ref_c8 %5 -> %arg1, @_QFwsloop_privateEi_private_ref_i32 %3 -> %arg2 : !llvm.ptr, !llvm.ptr) private_barrier {
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tblah wrote:

Thanks. I didn't know about that restriction. I've added a comment explaining.

https://github.com/llvm/llvm-project/pull/174105