[MLIR][OpenMP] Fix failing Lit tests (#242)

The omptarget-threadprivate-device-lowering.mlir test is updated with a valid
target triple to prevent triggering an assertion during translation to LLVM IR.

The openmp-todo.mlir test is updated, since unsupported simd clauses no longer
trigger errors but rather warnings. Messages triggered by these are also
updated to avoid misleading users.

Author: skatrak

mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp

@@ -32,6 +32,7 @@
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/ReplaceConstant.h"
 #include "llvm/Support/FileSystem.h"
+#include "llvm/Support/FormatVariadic.h"
 #include "llvm/TargetParser/Triple.h"
 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
 #include "llvm/Transforms/Utils/ModuleUtils.h"
@@ -525,7 +526,8 @@ static llvm::omp::ProcBindKind getProcBindKind(omp::ClauseProcBindKind kind) {
 /// been mapped to LLVM IR values.
 static LogicalResult
 convertIgnoredWrapper(omp::LoopWrapperInterface opInst,
-                      LLVM::ModuleTranslation &moduleTranslation) {
+                      LLVM::ModuleTranslation &moduleTranslation,
+                      const char *warningFmt) {
   // Map block arguments directly to the LLVM value associated to the
   // corresponding operand. This is semantically equivalent to this wrapper not
   // being present.
@@ -542,11 +544,11 @@ convertIgnoredWrapper(omp::LoopWrapperInterface opInst,
         forwardArgs(blockArgIface.getPrivateBlockArgs(), op.getPrivateVars());
         forwardArgs(blockArgIface.getReductionBlockArgs(),
                     op.getReductionVars());
-        op.emitWarning() << "simd information on composite construct discarded";
+        op.emitWarning() << llvm::formatv(warningFmt, "simd");
         return success();
       })
       .Default([&](Operation *op) {
-        return op->emitError() << "cannot ignore nested wrapper";
+        return op->emitError() << "cannot ignore wrapper";
       });
 }
 
@@ -567,7 +569,9 @@ convertIgnoredWrappers(omp::LoopNestOp loopOp,
   for (auto it =
            std::next(std::find(wrappers.rbegin(), wrappers.rend(), parentOp));
        it != wrappers.rend(); ++it) {
-    if (failed(convertIgnoredWrapper(*it, moduleTranslation)))
+    if (failed(convertIgnoredWrapper(
+            *it, moduleTranslation,
+            "{0} information on composite construct discarded")))
       return failure();
   }
 
@@ -2518,7 +2522,8 @@ convertOmpSimd(Operation &opInst, llvm::IRBuilderBase &builder,
 
   // This is needed to make sure that uses of entry block arguments for clauses
   // that are not going to be translated are mapped to the outside values.
-  if (failed(convertIgnoredWrapper(simdOp, moduleTranslation)))
+  if (failed(convertIgnoredWrapper(simdOp, moduleTranslation,
+                                   "{0} clauses ignored")))
     return failure();
 
   auto loopNestConversionResult = convertLoopNestHelper(

mlir/test/Target/LLVMIR/omptarget-threadprivate-device-lowering.mlir

@@ -4,7 +4,7 @@
 // omp.threadprivate does not crash on lowering during the OpenMP target device
 // pass when used in conjunction with target code in the same module.
 
-module attributes {omp.is_target_device = true } {
+module attributes {omp.is_target_device = true, llvm.target_triple = "amdgcn-amd-amdhsa"} {
   llvm.func @func() attributes {omp.declare_target = #omp.declaretarget<device_type = (host), capture_clause = (to)>} {
     %0 = llvm.mlir.addressof @_QFEpointer2 : !llvm.ptr
     %1 = omp.threadprivate %0 : !llvm.ptr -> !llvm.ptr
@@ -23,7 +23,7 @@ module attributes {omp.is_target_device = true } {
   }
 }
 
-// CHECK: define weak_odr protected void @{{.*}}(ptr %{{.*}}, ptr %[[ARG1:.*]]) {
+// CHECK: define weak_odr protected amdgpu_kernel void @{{.*}}(ptr %{{.*}}, ptr %[[ARG1:.*]]) #{{[0-9]+}} {
 // CHECK:  %[[ALLOCA:.*]] = alloca ptr, align 8
 // CHECK:  store ptr %[[ARG1]], ptr %[[ALLOCA]], align 8
 // CHECK:  %[[LOAD_ALLOCA:.*]] = load ptr, ptr %[[ALLOCA]], align 8

mlir/test/Target/LLVMIR/openmp-todo.mlir

@@ -175,8 +175,7 @@ llvm.func @sections_private(%x : !llvm.ptr) {
 // -----
 
 llvm.func @simd_linear(%lb : i32, %ub : i32, %step : i32, %x : !llvm.ptr) {
-  // expected-error@below {{not yet implemented: Unhandled clause linear in omp.simd operation}}
-  // expected-error@below {{LLVM Translation failed for operation: omp.simd}}
+  // expected-warning@below {{simd clauses ignored}}
   omp.simd linear(%x = %step : !llvm.ptr) {
     omp.loop_nest (%iv) : i32 = (%lb) to (%ub) step (%step) {
       omp.yield
@@ -188,8 +187,7 @@ llvm.func @simd_linear(%lb : i32, %ub : i32, %step : i32, %x : !llvm.ptr) {
 // -----
 
 llvm.func @simd_nontemporal(%lb : i32, %ub : i32, %step : i32, %x : !llvm.ptr) {
-  // expected-error@below {{not yet implemented: Unhandled clause nontemporal in omp.simd operation}}
-  // expected-error@below {{LLVM Translation failed for operation: omp.simd}}
+  // expected-warning@below {{simd clauses ignored}}
   omp.simd nontemporal(%x : !llvm.ptr) {
     omp.loop_nest (%iv) : i32 = (%lb) to (%ub) step (%step) {
       omp.yield
@@ -207,8 +205,7 @@ omp.private {type = private} @x.privatizer : !llvm.ptr alloc {
   omp.yield(%1 : !llvm.ptr)
 }
 llvm.func @simd_private(%lb : i32, %ub : i32, %step : i32, %x : !llvm.ptr) {
-  // expected-error@below {{not yet implemented: Unhandled clause privatization in omp.simd operation}}
-  // expected-error@below {{LLVM Translation failed for operation: omp.simd}}
+  // expected-warning@below {{simd clauses ignored}}
   omp.simd private(@x.privatizer %x -> %arg0 : !llvm.ptr) {
     omp.loop_nest (%iv) : i32 = (%lb) to (%ub) step (%step) {
       omp.yield
@@ -237,8 +234,7 @@ atomic {
   omp.yield
 }
 llvm.func @simd_reduction(%lb : i32, %ub : i32, %step : i32, %x : !llvm.ptr) {
-  // expected-error@below {{not yet implemented: Unhandled clause reduction in omp.simd operation}}
-  // expected-error@below {{LLVM Translation failed for operation: omp.simd}}
+  // expected-warning@below {{simd clauses ignored}}
   omp.simd reduction(@add_f32 %x -> %prv : !llvm.ptr) {
     omp.loop_nest (%iv) : i32 = (%lb) to (%ub) step (%step) {
       omp.yield