[PATCH] Add C/C++ attribute 'optnone'
Robinson, Paul
Paul_Robinson at playstation.sony.com
Tue Nov 19 17:56:16 PST 2013
Revised patch with requested changes to allow 'optnone' on an
ObjC method.
--paulr
> -----Original Message-----
> From: aaron.ballman at gmail.com [mailto:aaron.ballman at gmail.com] On Behalf
> Of Aaron Ballman
> Sent: Tuesday, November 19, 2013 5:11 PM
> To: Robinson, Paul
> Cc: cfe-commits at cs.uiuc.edu cfe
> Subject: Re: [PATCH] Add C/C++ attribute 'optnone'
>
> On Tue, Nov 19, 2013 at 6:33 PM, Robinson, Paul
> <Paul_Robinson at playstation.sony.com> wrote:
> >> -----Original Message-----
> >> From: aaron.ballman at gmail.com [mailto:aaron.ballman at gmail.com] On
> Behalf
> >> Of Aaron Ballman
> >> Sent: Tuesday, November 19, 2013 2:36 PM
> >> To: Robinson, Paul
> >> Cc: cfe-commits at cs.uiuc.edu cfe
> >> Subject: Re: [PATCH] Add C/C++ attribute 'optnone'
> >>
> >> > Index: include/clang/Basic/Attr.td
> >> > ===================================================================
> >> > --- include/clang/Basic/Attr.td (revision 195153)
> >> > +++ include/clang/Basic/Attr.td (working copy)
> >> > @@ -613,6 +613,11 @@
> >> > let Subjects = [ObjCInterface];
> >> > }
> >> >
> >> > +def OptimizeNone : InheritableAttr {
> >> > + let Spellings = [GNU<"optnone">, CXX11<"clang", "optnone">];
> >> > + let Subjects = [Function];
> >>
> >> Can it apply to ObjC method declarations as well, or just functions?
> >
> > Um. Hadn't thought about it as ObjC isn't my use case. It can apply
> > to C++ methods, so I guess it could? What do I do to make that work?
>
> In Attr.td, add ObjCMethod to the list of subjects, and in
> SemaDeclAttr.cpp, check for ObjCMethodDecl alongside of the existing
> FunctionDecl (and switch to using ExpectedFunctionOrMethod). I would
> guess this attribute does apply to ObjC methods, so this strikes me as
> a reasonable extension.
> >
> >>
> >> > +}
> >> > +
> >> > def Overloadable : Attr {
> >> > let Spellings = [GNU<"overloadable">];
> >> > }
> >> > Index: lib/CodeGen/CodeGenModule.cpp
> >> > ===================================================================
> >> > --- lib/CodeGen/CodeGenModule.cpp (revision 195153)
> >> > +++ lib/CodeGen/CodeGenModule.cpp (working copy)
> >> > @@ -678,6 +678,10 @@
> >> > // Naked implies noinline: we should not be inlining such
> >> functions.
> >> > B.addAttribute(llvm::Attribute::Naked);
> >> > B.addAttribute(llvm::Attribute::NoInline);
> >> > + } else if (D->hasAttr<OptimizeNoneAttr>()) {
> >> > + // OptimizeNone implies noinline; we should not be inlining
> such
> >> functions.
> >> > + B.addAttribute(llvm::Attribute::OptimizeNone);
> >> > + B.addAttribute(llvm::Attribute::NoInline);
> >> > } else if (D->hasAttr<NoInlineAttr>()) {
> >> > B.addAttribute(llvm::Attribute::NoInline);
> >> > } else if ((D->hasAttr<AlwaysInlineAttr>() ||
> >> > @@ -696,6 +700,12 @@
> >> > if (D->hasAttr<MinSizeAttr>())
> >> > B.addAttribute(llvm::Attribute::MinSize);
> >> >
> >> > + if (D->hasAttr<OptimizeNoneAttr>()) {
> >> > + // OptimizeNone wins over OptimizeForSize and MinSize.
> >> > + B.removeAttribute(llvm::Attribute::OptimizeForSize);
> >> > + B.removeAttribute(llvm::Attribute::MinSize);
> >>
> >> Is this something we should warn the user on when we encounter a
> >> minsize attribute along with an optnone attribute? Or should this be
> >> mutually exclusive like in the case of optnone and alwaysinline?
> >
> > See reply to Richard.
> >
> >>
> >> > + }
> >> > +
> >> > if (LangOpts.getStackProtector() == LangOptions::SSPOn)
> >> > B.addAttribute(llvm::Attribute::StackProtect);
> >> > else if (LangOpts.getStackProtector() == LangOptions::SSPReq)
> >> > Index: lib/Sema/SemaDeclAttr.cpp
> >> > ===================================================================
> >> > --- lib/Sema/SemaDeclAttr.cpp (revision 195153)
> >> > +++ lib/Sema/SemaDeclAttr.cpp (working copy)
> >> > @@ -1764,6 +1764,12 @@
> >> > return;
> >> > }
> >> >
> >> > + if (D->hasAttr<OptimizeNoneAttr>()) {
> >> > + S.Diag(Attr.getLoc(), diag::err_attributes_are_not_compatible)
> >> > + << Attr.getName() << "'optnone'";
> >>
> >> This is not a grumble for you to fix, but it would be very nice if we
> >> could get the original spelling for this diagnostic instead of
> >> hard-coding one particular spelling.
> >
> > Ayup.
> >
> >>
> >> > + return;
> >> > + }
> >> > +
> >> > D->addAttr(::new (S.Context)
> >> > AlwaysInlineAttr(Attr.getRange(), S.Context,
> >> >
> Attr.getAttributeSpellingListIndex()));
> >> > @@ -3637,6 +3643,25 @@
> >> > Attr.getAttributeSpellingListIndex()));
> >> > }
> >> >
> >> > +static void handleOptimizeNoneAttr(Sema &S, Decl *D,
> >> > + const AttributeList &Attr) {
> >> > + if (!isa<FunctionDecl>(D)) {
> >> > + S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
> >> > + << Attr.getName() << ExpectedFunction;
> >> > + return;
> >> > + }
> >> > +
> >> > + if (D->hasAttr<AlwaysInlineAttr>()) {
> >> > + S.Diag(Attr.getLoc(), diag::err_attributes_are_not_compatible)
> >> > + << Attr.getName() << "'always_inline'";
> >> > + return;
> >> > + }
> >> > +
> >> > + D->addAttr(::new (S.Context)
> >> > + OptimizeNoneAttr(Attr.getRange(), S.Context,
> >> > +
> Attr.getAttributeSpellingListIndex()));
> >> > +}
> >> > +
> >> > static void handleNoInstrumentFunctionAttr(Sema &S, Decl *D,
> >> > const AttributeList
> &Attr)
> >> {
> >> > if (!isa<FunctionDecl>(D)) {
> >> > @@ -4662,6 +4687,9 @@
> >> > case AttributeList::AT_MinSize:
> >> > handleMinSizeAttr(S, D, Attr);
> >> > break;
> >> > + case AttributeList::AT_OptimizeNone:
> >> > + handleOptimizeNoneAttr(S, D, Attr);
> >> > + break;
> >> > case AttributeList::AT_Format: handleFormatAttr (S, D,
> >> Attr); break;
> >> > case AttributeList::AT_FormatArg: handleFormatArgAttr (S, D,
> >> Attr); break;
> >> > case AttributeList::AT_CUDAGlobal: handleGlobalAttr (S, D,
> >> Attr); break;
> >> > Index: test/CodeGen/attr-optnone.c
> >> > ===================================================================
> >> > --- test/CodeGen/attr-optnone.c (revision 0)
> >> > +++ test/CodeGen/attr-optnone.c (revision 0)
> >> > @@ -0,0 +1,26 @@
> >> > +// RUN: %clang_cc1 -fms-compatibility -emit-llvm < %s > %t
> >> > +// RUN: FileCheck %s --check-prefix=PRESENT < %t
> >> > +// RUN: FileCheck %s --check-prefix=ABSENT < %t
> >> > +
> >> > +__attribute__((optnone)) __forceinline
> >> > +int test2() { return 0; }
> >> > +// PRESENT-DAG: @test2{{.*}}[[ATTR2:#[0-9]+]]
> >> > +
> >> > +__attribute__((optnone)) __attribute__((minsize))
> >> > +int test3() { return 0; }
> >> > +// PRESENT-DAG: @test3{{.*}}[[ATTR3:#[0-9]+]]
> >> > +
> >> > +__attribute__((optnone)) __attribute__((cold))
> >> > +int test4() { return test2(); }
> >> > +// PRESENT-DAG: @test4{{.*}}[[ATTR4:#[0-9]+]]
> >> > +// Also check that test2 isn't inlined into test4 (optnone trumps
> >> forceinline).
> >> > +// PRESENT-DAG: call i32 @test2
> >> > +
> >> > +// Check that we set both attributes noinline and optnone on each
> >> function.
> >> > +// PRESENT-DAG: attributes [[ATTR2]] = {
> >> {{.*}}noinline{{.*}}optnone{{.*}} }
> >> > +// PRESENT-DAG: attributes [[ATTR3]] = {
> >> {{.*}}noinline{{.*}}optnone{{.*}} }
> >> > +// PRESENT-DAG: attributes [[ATTR4]] = {
> >> {{.*}}noinline{{.*}}optnone{{.*}} }
> >> > +
> >> > +// Check that no 'optsize' or 'minsize' attributes appear.
> >> > +// ABSENT-NOT: optsize
> >> > +// ABSENT-NOT: minsize
> >> > Index: test/SemaCXX/attr-optnone.cpp
> >> > ===================================================================
> >> > --- test/SemaCXX/attr-optnone.cpp (revision 0)
> >> > +++ test/SemaCXX/attr-optnone.cpp (revision 0)
> >> > @@ -0,0 +1,44 @@
> >> > +// RUN: %clang_cc1 -std=c++11 -fms-compatibility -fsyntax-only -
> >> verify %s
> >> > +
> >> > +int foo() __attribute__((optnone));
> >> > +int bar() __attribute__((optnone)) __attribute__((noinline));
> >> > +
> >> > +int baz() __attribute__((always_inline)) __attribute__((optnone));
> //
> >> expected-error{{'always_inline' and 'optnone' attributes are not
> >> compatible}}
> >> > +int qux() __attribute__((optnone)) __attribute__((always_inline));
> //
> >> expected-error{{'optnone' and 'always_inline' attributes are not
> >> compatible}}
> >> > +
> >> > +int globalVar __attribute__((optnone)); // expected-
> >> warning{{'optnone' attribute only applies to functions}}
> >> > +
> >> > +int fubar(int __attribute__((optnone)), int); // expected-
> >> warning{{'optnone' attribute only applies to functions}}
> >> > +
> >> > +struct A {
> >> > + int aField __attribute__((optnone)); // expected-
> >> warning{{'optnone' attribute only applies to functions}}
> >> > +};
> >> > +
> >> > +struct B {
> >> > + void foo() __attribute__((optnone));
> >> > + static void bar() __attribute__((optnone));
> >> > +};
> >> > +
> >> > +// Verify that we can specify the [[clang::optnone]] syntax as
> well.
> >> > +
> >> > +[[clang::optnone]]
> >> > +int foo2();
> >> > +[[clang::optnone]]
> >> > +int bar2() __attribute__((noinline));
> >> > +
> >> > +[[clang::optnone]]
> >> > +int baz2() __attribute__((always_inline)); // expected-
> >> error{{'always_inline' and 'optnone' attributes are not compatible}}
> >> > +
> >> > +[[clang::optnone]] int globalVar2; //expected-warning{{'optnone'
> >> attribute only applies to functions}}
> >> > +
> >> > +struct A2 {
> >> > + [[clang::optnone]] int aField; // expected-warning{{'optnone'
> >> attribute only applies to functions}}
> >> > +};
> >> > +
> >> > +struct B2 {
> >> > + [[clang::optnone]]
> >> > + void foo();
> >> > + [[clang::optnone]]
> >> > + static void bar();
> >> > +};
> >> > +
> >> >
> >>
> >> ~Aaron
> >>
> >> On Tue, Nov 19, 2013 at 5:25 PM, Robinson, Paul
> >> <Paul_Robinson at playstation.sony.com> wrote:
> >> > Adds a new ‘optnone’ function attribute that maps directly to the
> LLVM
> >> IR
> >> > ‘optnone’ attribute.
> >> >
> >> > --paulr
> >> >
> >> >
> >> >
> >> >
> >> > _______________________________________________
> >> > cfe-commits mailing list
> >> > cfe-commits at cs.uiuc.edu
> >> > http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
> >> >
> >
>
> ~Aaron
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