remove counter-intuitive modifications of inline attributes

include/clang/Basic/CodeGenOptions.def

@@ -152,9 +152,6 @@ CODEGENOPT(FatalWarnings     , 1, 0) ///< Set when -Wa,--fatal-warnings is
 CODEGENOPT(EnableSegmentedStacks , 1, 0) ///< Set when -fsplit-stack is enabled.
 CODEGENOPT(NoImplicitFloat   , 1, 0) ///< Set when -mno-implicit-float is enabled.
 CODEGENOPT(NoInfsFPMath      , 1, 0) ///< Assume FP arguments, results not +-Inf.
-CODEGENOPT(NoInline          , 1, 0) ///< Set when -fno-inline is enabled. 
-                                     ///< Disables use of the inline keyword.
-CODEGENOPT(ForceNoInline, 1, 1) ///< Set noinline as the default attribute
 CODEGENOPT(NoSignedZeros     , 1, 0) ///< Allow ignoring the signedness of FP zero
 CODEGENOPT(NullPointerIsValid , 1, 0) ///< Assume Null pointer deference is defined.
 CODEGENOPT(Reassociate       , 1, 0) ///< Allow reassociation of FP math ops

lib/CodeGen/CodeGenFunction.cpp

@@ -862,34 +862,15 @@ void CodeGenFunction::StartFunction(GlobalDecl GD,
   assert(CurFn->isDeclaration() && "Function already has body?");
 
   // Pass inline keyword to optimizer if it appears explicitly on any
-  // declaration. Also, in the case of -fno-inline attach NoInline
-  // attribute to all function that are not marked AlwaysInline.
+  // declaration.
   if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
-    if (!CGM.getCodeGenOpts().NoInline) {
-      for (auto RI : FD->redecls())
-        if (RI->isInlineSpecified()) {
-          // For MDF CM, emit inline attribute as alwaysinline.
-          if (getLangOpts().MdfCM)
-            Fn->addFnAttr(llvm::Attribute::AlwaysInline);
-          else
-            Fn->addFnAttr(llvm::Attribute::InlineHint);
-          break;
-        }
-    } else if (!FD->hasAttr<AlwaysInlineAttr>())
-      Fn->addFnAttr(llvm::Attribute::NoInline);
-
-    // For a GenX function if it is not alwaysinline, it will be noinline to
-    // match the old compiler's behavior. This behavior can be overwritten
-    // with option -fno-force-noinline.
-    //
-    // For C++ members, make them always inline to optimize away this pointer.
-    if (getLangOpts().MdfCM && FD->isCXXInstanceMember())
-      Fn->addFnAttr(llvm::Attribute::AlwaysInline);
-
-    if (getLangOpts().MdfCM &&
-        CGM.getCodeGenOpts().ForceNoInline &&
-        !Fn->getAttributes().hasAttrSomewhere(llvm::Attribute::AlwaysInline))
-      Fn->addFnAttr(llvm::Attribute::NoInline);
+    for (auto RI : FD->redecls()) {
+      if (RI->isInlineSpecified()) {
+        // For MDF CM, emit inline attribute as alwaysinline.
+        if (getLangOpts().MdfCM)
+          Fn->addFnAttr(llvm::Attribute::AlwaysInline);
+      }
+    }
   }
 
   // Finer control on the loop info for MDF cm.

lib/Frontend/CompilerInvocation.cpp

@@ -779,8 +779,6 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
       Args.hasFlag(OPT_funroll_loops, OPT_fno_unroll_loops,
                    (Opts.OptimizationLevel > 1));
 
-  // For CM only, set as noinline for functions without inline attribute.
-  Opts.ForceNoInline = !Args.hasArg(OPT_fno_force_noinline);
   if (Args.hasArg(OPT_mCM_import_bif))
     Opts.GenXBiFName = Args.getLastArgValue(OPT_mCM_import_bif);
   // By default, CM global variables are not default initialized, this option

test/CMFE/compiler_options/Ox_modes.cpp

@@ -0,0 +1,45 @@
+/*========================== begin_copyright_notice ============================
+
+Copyright (C) 2021 Intel Corporation
+
+SPDX-License-Identifier: MIT
+
+============================= end_copyright_notice ===========================*/
+
+// RUN: IGC_CMFE_CC1_EXTRA="-O2;-disable-llvm-passes" %cmc -fcmocl -march=skl -emit-llvm -S -o %t.ll -- %s
+// RUN: FileCheck --input-file=%t.ll %s --check-prefixes=MODE_O2,MODE_O2_NO_NOINLINE
+// RUN: FileCheck --input-file=%t.ll %s --check-prefixes=MODE_O2,MODE_O2_NO_OPTNONE
+// MODE_O2: subgroup_8{{.*}}#[[SUBGROUP_ATTR:[0-9]+]]
+// MODE_O2: attributes #[[SUBGROUP_ATTR]] = {
+// MODE_O2_NO_NOINLINE-NOT: noinline
+// MODE_O2_NO_OPTNONE-NOT: optnone
+// MODE_O2-SAME: }
+
+// RUN: %cmc -fcmocl -march=skl -emit-llvm -S -o %t.ll -- %s
+// RUN: FileCheck --input-file=%t.ll %s --check-prefixes=MODE_O0,MODE_O0_NOINLINE
+// RUN: FileCheck --input-file=%t.ll %s --check-prefixes=MODE_O0,MODE_O0_OPTNONE
+// MODE_O0: subgroup_8{{.*}}#[[SUBGROUP_ATTR:[0-9]+]]
+// MODE_O0: attributes #[[SUBGROUP_ATTR]] = {
+// MODE_O0_NOINLINE-SAME: noinline
+// MODE_O0_OPTNONE-SAME: optnone
+
+#include <cm/cm.h>
+
+int S1(vector<int, 8> v_out) {
+  return v_out[0];
+}
+
+extern "C" _GENX_MAIN_ void subgroup_8(
+    SurfaceIndex L [[type("buffer_t")]],
+    SurfaceIndex R [[type("buffer_t")]],
+    SurfaceIndex Res  [[type("buffer_t")]]
+) {
+    vector<int64_t, 8> l;
+    vector<int64_t, 8> res;
+
+    read(L, 0, l);
+    res = S1(l);
+
+    write(Res, 0, res);
+}
+