[llvm] 989674f - [OpenMP] Ensure to remove noinline from all runtime functions eventually

[Johannes Doerfert via llvm-commits]

Author: Johannes Doerfert
Date: 2022-02-01T01:07:50-06:00
New Revision: 989674f110548866f149b964288d8a84f0d60f40

URL: https://github.com/llvm/llvm-project/commit/989674f110548866f149b964288d8a84f0d60f40
DIFF: https://github.com/llvm/llvm-project/commit/989674f110548866f149b964288d8a84f0d60f40.diff

LOG: [OpenMP] Ensure to remove noinline from all runtime functions eventually

We used to remove noinline from known OpenMP runtime functions (which
are declared in OMPKinds.td). Now we remove noinline from all functions
with the proper prefixes: __kmpc, _ZN4_OMP (= namespace omp), omp_

Added: 
    llvm/test/Transforms/OpenMP/remove_noinline_attributes.ll

Modified: 
    llvm/lib/Transforms/IPO/OpenMPOpt.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/IPO/OpenMPOpt.cpp b/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
index 68f33410c602e..20045502db459 100644
--- a/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
+++ b/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
@@ -458,7 +458,6 @@ struct OMPInformationCache : public InformationCache {
     RTLFunctions.insert(F);                                                    \
     if (declMatchesRTFTypes(F, OMPBuilder._ReturnType, ArgsTypes)) {           \
       RuntimeFunctionIDMap[F] = _Enum;                                         \
-      F->removeFnAttr(Attribute::NoInline);                                    \
       auto &RFI = RFIs[_Enum];                                                 \
       RFI.Kind = _Enum;                                                        \
       RFI.Name = _Name;                                                        \
@@ -480,6 +479,15 @@ struct OMPInformationCache : public InformationCache {
   }
 #include "llvm/Frontend/OpenMP/OMPKinds.def"
 
+    // Remove the `noinline` attribute from `__kmpc`, `_OMP::` and `omp_`
+    // functions, except if `optnone` is present.
+    for (Function &F : M) {
+      for (StringRef Prefix : {"__kmpc", "_ZN4_OMP", "omp_"})
+        if (F.getName().startswith(Prefix) &&
+            !F.hasFnAttribute(Attribute::OptimizeNone))
+          F.removeFnAttr(Attribute::NoInline);
+    }
+
     // TODO: We should attach the attributes defined in OMPKinds.def.
   }
 

diff  --git a/llvm/test/Transforms/OpenMP/remove_noinline_attributes.ll b/llvm/test/Transforms/OpenMP/remove_noinline_attributes.ll
new file mode 100644
index 0000000000000..76c506334f0ea
--- /dev/null
+++ b/llvm/test/Transforms/OpenMP/remove_noinline_attributes.ll
@@ -0,0 +1,98 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-attributes
+; RUN: opt < %s -S -openmp-opt-cgscc        | FileCheck %s
+; RUN: opt < %s -S -passes=openmp-opt-cgscc | FileCheck %s
+
+declare void @unknown()
+
+; __kmpc functions
+define void @__kmpc_noinline() noinline nounwind {
+; CHECK: Function Attrs: nounwind
+; CHECK-LABEL: @__kmpc_noinline(
+; CHECK-NEXT:    call void @unknown()
+; CHECK-NEXT:    ret void
+;
+  call void @unknown()
+  ret void
+}
+; omp_X functions
+define void @omp_noinline() noinline nounwind {
+; CHECK: Function Attrs: nounwind
+; CHECK-LABEL: @omp_noinline(
+; CHECK-NEXT:    call void @unknown()
+; CHECK-NEXT:    ret void
+;
+  call void @unknown()
+  ret void
+}
+; _OMP namespace
+define void @_ZN4_OMP_noinline() noinline nounwind {
+; CHECK: Function Attrs: nounwind
+; CHECK-LABEL: @_ZN4_OMP_noinline(
+; CHECK-NEXT:    call void @unknown()
+; CHECK-NEXT:    ret void
+;
+  call void @unknown()
+  ret void
+}
+
+; Negative tests:
+
+define void @__kmpc_noinline_optnone() noinline optnone nounwind {
+; CHECK: Function Attrs: noinline nounwind optnone
+; CHECK-LABEL: @__kmpc_noinline_optnone(
+; CHECK-NEXT:    call void @unknown()
+; CHECK-NEXT:    ret void
+;
+  call void @unknown()
+  ret void
+}
+define void @omp_noinline_optnone() noinline optnone nounwind {
+; CHECK: Function Attrs: noinline nounwind optnone
+; CHECK-LABEL: @omp_noinline_optnone(
+; CHECK-NEXT:    call void @unknown()
+; CHECK-NEXT:    ret void
+;
+  call void @unknown()
+  ret void
+}
+; _OMP namespace
+define void @_ZN4_OMP_noinline_optnone() noinline optnone nounwind {
+; CHECK: Function Attrs: noinline nounwind optnone
+; CHECK-LABEL: @_ZN4_OMP_noinline_optnone(
+; CHECK-NEXT:    call void @unknown()
+; CHECK-NEXT:    ret void
+;
+  call void @unknown()
+  ret void
+}
+define void @a___kmpc_noinline() noinline nounwind {
+; CHECK: Function Attrs: noinline nounwind
+; CHECK-LABEL: @a___kmpc_noinline(
+; CHECK-NEXT:    call void @unknown()
+; CHECK-NEXT:    ret void
+;
+  call void @unknown()
+  ret void
+}
+define void @a_omp_noinline() noinline nounwind {
+; CHECK: Function Attrs: noinline nounwind
+; CHECK-LABEL: @a_omp_noinline(
+; CHECK-NEXT:    call void @unknown()
+; CHECK-NEXT:    ret void
+;
+  call void @unknown()
+  ret void
+}
+define void @a__ZN4_OMP_noinline() noinline nounwind {
+; CHECK: Function Attrs: noinline nounwind
+; CHECK-LABEL: @a__ZN4_OMP_noinline(
+; CHECK-NEXT:    call void @unknown()
+; CHECK-NEXT:    ret void
+;
+  call void @unknown()
+  ret void
+}
+
+!llvm.module.flags = !{!0}
+
+!0 = !{i32 7, !"openmp", i32 50}