[flang] [llvm] [mlir] [OpenMPIRBuilder] Don't drop debug info for target region. (PR #80692)

[Kiran Chandramohan via llvm-commits]

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@@ -0,0 +1,72 @@
+// RUN: mlir-translate -mlir-to-llvmir %s | FileCheck %s
+
+module attributes {omp.is_target_device = true} {
+  llvm.func @_QQmain() {
+    %0 = llvm.mlir.constant(1 : i64) : i64
+    %1 = llvm.alloca %0 x i32 : (i64) -> !llvm.ptr<5>
+    %2 = llvm.addrspacecast %1 : !llvm.ptr<5> to !llvm.ptr
+    %3 = llvm.mlir.constant(1 : i64) : i64
+    %4 = llvm.alloca %3 x i32 : (i64) -> !llvm.ptr<5>
+    %5 = llvm.addrspacecast %4 : !llvm.ptr<5> to !llvm.ptr
+    %6 = llvm.mlir.constant(1 : i64) : i64
+    %7 = llvm.alloca %6 x i32 : (i64) -> !llvm.ptr<5>
+    %8 = llvm.addrspacecast %7 : !llvm.ptr<5> to !llvm.ptr
+    %9 = omp.map_info var_ptr(%2 : !llvm.ptr, i32) map_clauses(tofrom) capture(ByRef) -> !llvm.ptr {name = ""}
+    %10 = omp.map_info var_ptr(%5 : !llvm.ptr, i32) map_clauses(tofrom) capture(ByRef) -> !llvm.ptr {name = ""}
+    omp.target map_entries(%9 -> %arg0, %10 -> %arg1 : !llvm.ptr, !llvm.ptr) {
+    ^bb0(%arg0: !llvm.ptr, %arg1: !llvm.ptr):
+      %12 = llvm.mlir.constant(2 : i32) : i32
+      %13 = llvm.mlir.constant(1 : i32) : i32
+      %14 = llvm.load %arg0 : !llvm.ptr -> i32 loc(#loc2)
+      %15 = llvm.add %14, %13  : i32 loc(#loc2)
+      llvm.store %15, %arg0 : i32, !llvm.ptr loc(#loc2)
+      %16 = llvm.load %arg0 : !llvm.ptr -> i32 loc(#loc3)
+      %17 = llvm.add %16, %12  : i32 loc(#loc3)
+      llvm.store %17, %arg1 : i32, !llvm.ptr loc(#loc3)
+      omp.terminator
+    }
+    %11 = omp.map_info var_ptr(%8 : !llvm.ptr, i32) map_clauses(tofrom) capture(ByRef) -> !llvm.ptr {name = ""}
+    omp.target map_entries(%11 -> %arg0 : !llvm.ptr) {
+    ^bb0(%arg0: !llvm.ptr):
+      %12 = llvm.mlir.constant(1 : i32) : i32
+      omp.parallel {
+        %13 = llvm.load %arg0 : !llvm.ptr -> i32 loc(#loc4)
+        %14 = llvm.add %13, %12  : i32 loc(#loc4)
+        llvm.store %14, %arg0 : i32, !llvm.ptr loc(#loc4)
+        omp.terminator
+      }
+      omp.terminator
+    }
+    llvm.return
+  } loc(#loc5)
+} loc(#loc)
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kiranchandramohan wrote:

Nit: can you minimize this testcase to be as small as possible? We do not need a large region particularly.

https://github.com/llvm/llvm-project/pull/80692