[llvm] 74cacf2 - [OpenMP] Add RTL function to externalization RAII

[Joseph Huber via llvm-commits]

Author: Joseph Huber
Date: 2022-02-17T14:30:58-05:00
New Revision: 74cacf212bb31f8ba837b7eb2434258dd79eaccb

URL: https://github.com/llvm/llvm-project/commit/74cacf212bb31f8ba837b7eb2434258dd79eaccb
DIFF: https://github.com/llvm/llvm-project/commit/74cacf212bb31f8ba837b7eb2434258dd79eaccb.diff

LOG: [OpenMP] Add RTL function to externalization RAII

This patch adds the '_kmpc_get_hardware_num_threads_in_block'
OpenMP RTL function to the externalization RAII struct. This was getting
optimized out and then being replaced with an undefined value once added
back in, causing bugs for complex reductions.

Fixes #53909.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D120076

Added: 
    

Modified: 
    llvm/lib/Transforms/IPO/OpenMPOpt.cpp
    llvm/test/Transforms/OpenMP/get_hardware_num_threads_in_block_fold.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/IPO/OpenMPOpt.cpp b/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
index f577a6b0f1743..392b919c5a120 100644
--- a/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
+++ b/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
@@ -2119,6 +2119,8 @@ struct OpenMPOpt {
                                        OMPRTL___kmpc_barrier_simple_generic);
     ExternalizationRAII ThreadId(OMPInfoCache,
                                  OMPRTL___kmpc_get_hardware_thread_id_in_block);
+    ExternalizationRAII NumThreads(
+        OMPInfoCache, OMPRTL___kmpc_get_hardware_num_threads_in_block);
     ExternalizationRAII WarpSize(OMPInfoCache, OMPRTL___kmpc_get_warp_size);
 
     registerAAs(IsModulePass);

diff  --git a/llvm/test/Transforms/OpenMP/get_hardware_num_threads_in_block_fold.ll b/llvm/test/Transforms/OpenMP/get_hardware_num_threads_in_block_fold.ll
index b72031a9b68c0..57eaebc7e141c 100644
--- a/llvm/test/Transforms/OpenMP/get_hardware_num_threads_in_block_fold.ll
+++ b/llvm/test/Transforms/OpenMP/get_hardware_num_threads_in_block_fold.ll
@@ -178,7 +178,16 @@ entry:
   ret void
 }
 
-declare i32 @__kmpc_get_hardware_num_threads_in_block()
+define internal i32 @__kmpc_get_hardware_num_threads_in_block() {
+; CHECK-LABEL: define {{[^@]+}}@__kmpc_get_hardware_num_threads_in_block
+; CHECK-SAME: () #[[ATTR1]] {
+; CHECK-NEXT:    [[RET:%.*]] = call i32 @__kmpc_get_hardware_num_threads_in_block_dummy()
+; CHECK-NEXT:    ret i32 [[RET]]
+;
+  %ret = call i32 @__kmpc_get_hardware_num_threads_in_block_dummy()
+  ret i32 %ret
+}
+declare i32 @__kmpc_get_hardware_num_threads_in_block_dummy()
 declare i32 @__kmpc_target_init(%struct.ident_t*, i8, i1 zeroext, i1 zeroext) #1
 declare void @__kmpc_target_deinit(%struct.ident_t* nocapture readnone, i8, i1 zeroext) #1
 declare void @__kmpc_parallel_51(%struct.ident_t*, i32, i32, i32, i32, i8*, i8*, i8**, i64)