Accepting request 204367 from devel:ARM:Factory

- add r189852.diff: Remove vtables optimisation that breaks ARM
  and PowerPC
- Disable testsuite on ARMv7, takes forever to run

OBS-URL: https://build.opensuse.org/request/show/204367
OBS-URL: https://build.opensuse.org/package/show/devel:tools:compiler/llvm?expand=0&rev=286

_constraints

@@ -1,10 +0,0 @@
-<?xml version="1.0"?>
-<constraints>
-  <hardware>
-    <physicalmemory>
-      <size unit="M">2000</size>
-    </physicalmemory>
-  </hardware>
-  <sandbox>kvm</sandbox>
-  <hostlabel exclude="true">SLOW_CPU</hostlabel>
-</constraints>

llvm.changes

@@ -1,3 +1,10 @@
+-------------------------------------------------------------------
+Tue Oct 22 20:57:00 UTC 2013 - dmueller@suse.com
+
+- add r189852.diff: Remove vtables optimisation that breaks ARM
+  and PowerPC
+- Disable testsuite on ARMv7, takes forever to run
+
 -------------------------------------------------------------------
 Thu Oct 17 10:23:32 UTC 2013 - schwab@suse.de
 

llvm.spec

@@ -63,6 +63,7 @@ Patch10:        llvm-no-visibility.patch
 # PATCH-FIX-OPENSUSE llvm-disable-pretty-stack-trace.patch -- https://bugs.freedesktop.org/show_bug.cgi?id=60929
 Patch11:        llvm-disable-pretty-stack-trace.patch
 Patch12:        arm-remove-xfails.diff
+Patch13:        r189852.diff
 BuildRoot:      %{_tmppath}/%{name}-%{version}-build
 BuildRequires:  autoconf
 BuildRequires:  automake
@@ -176,6 +177,7 @@ This package contains vim plugins for LLVM like syntax highlighting.
 %endif
 %patch11 -p1
 %patch12
+%patch13
 
 # We hardcode i586
 rm tools/clang/test/Driver/x86_features.c
@@ -304,6 +306,7 @@ make %{?_smp_mflags} VERBOSE=1
 
 %check
 cd stage2
+%ifnarch armv7hl armv7l
 %if 0%{!?qemu_user_space_build:1}
 # we just do not have enough memory with qemu emulation
 
@@ -325,6 +328,7 @@ done
 make check
 make clang-test
 %endif
+%endif
 
 %install
 cd stage2

r189852.diff

@@ -0,0 +1,188 @@
+
+Don't emit an available_externally vtable pointing to linkonce_odr funcs.
+
+This fixes pr13124.
+
+From the discussion at
+http://lists.cs.uiuc.edu/pipermail/cfe-dev/2012-June/022606.html
+we know that we cannot make funcions in a weak_odr vtable also weak_odr. They
+should remain linkonce_odr.
+
+The side effect is that we cannot emit a available_externally vtable unless we
+also emit a copy of the function. This also has an issue: If codegen is going
+to output a function, sema has to mark it used. Given llvm.org/pr9114, it looks
+like sema cannot be more aggressive at marking functions used because
+of vtables.
+
+This leaves us with a few unpleasant options:
+
+* Marking functions in vtables used if possible. This sounds a bit sloppy, so
+  we should avoid it.
+* Producing available_externally vtables only when all the functions in it are
+  already used or weak_odr. This would cover cases like
+
+--------------------
+struct foo {
+  virtual ~foo();
+};
+struct bar : public foo {
+  virtual void zed();
+};
+void f() {
+  foo *x(new bar);
+  delete x;
+}
+void g(bar *x) {
+  x->~bar(); // force the destructor to be used
+}
+--------------------------
+
+and
+
+----------------------------------
+template<typename T>
+struct bar {
+  virtual ~bar();
+};
+template<typename T>
+bar<T>::~bar() {
+}
+
+// make the destructor weak_odr instead of linkonce_odr
+extern template class bar<int>;
+
+void f() {
+  bar<int> *x(new bar<int>);
+  delete x;
+}
+----------------------------
+
+These look like corner cases, so it is unclear if it is worth it.
+
+* And finally: Just nuke this optimization. That is what this patch implements.
+
+
+--- tools/clang/lib/CodeGen/CGVTables.cpp
++++ tools/clang/lib/CodeGen/CGVTables.cpp
+@@ -734,12 +734,7 @@
+     switch (keyFunction->getTemplateSpecializationKind()) {
+       case TSK_Undeclared:
+       case TSK_ExplicitSpecialization:
+-        // When compiling with optimizations turned on, we emit all vtables,
+-        // even if the key function is not defined in the current translation
+-        // unit. If this is the case, use available_externally linkage.
+-        if (!def && CodeGenOpts.OptimizationLevel)
+-          return llvm::GlobalVariable::AvailableExternallyLinkage;
+-
++        assert(def && "Should not have been asked to emit this");
+         if (keyFunction->isInlined())
+           return !Context.getLangOpts().AppleKext ?
+                    llvm::GlobalVariable::LinkOnceODRLinkage :
+@@ -758,9 +753,7 @@
+                  llvm::Function::InternalLinkage;
+   
+       case TSK_ExplicitInstantiationDeclaration:
+-        return !Context.getLangOpts().AppleKext ?
+-                 llvm::GlobalVariable::AvailableExternallyLinkage :
+-                 llvm::Function::InternalLinkage;
++        llvm_unreachable("Should not have been asked to emit this");
+     }
+   }
+ 
+@@ -776,7 +769,7 @@
+     return llvm::GlobalVariable::LinkOnceODRLinkage;
+ 
+   case TSK_ExplicitInstantiationDeclaration:
+-    return llvm::GlobalVariable::AvailableExternallyLinkage;
++    llvm_unreachable("Should not have been asked to emit this");
+ 
+   case TSK_ExplicitInstantiationDefinition:
+       return llvm::GlobalVariable::WeakODRLinkage;
+@@ -875,16 +868,6 @@
+ /// we define that v-table?
+ static bool shouldEmitVTableAtEndOfTranslationUnit(CodeGenModule &CGM,
+                                                    const CXXRecordDecl *RD) {
+-  // If we're building with optimization, we always emit v-tables
+-  // since that allows for virtual function calls to be devirtualized.
+-  // If the v-table is defined strongly elsewhere, this definition
+-  // will be emitted available_externally.
+-  //
+-  // However, we don't want to do this in -fapple-kext mode, because
+-  // kext mode does not permit devirtualization.
+-  if (CGM.getCodeGenOpts().OptimizationLevel && !CGM.getLangOpts().AppleKext)
+-    return true;
+-
+   return !CGM.getVTables().isVTableExternal(RD);
+ }
+ 
+--- tools/clang/test/CodeGenCXX/thunks-available-externally.cpp
++++ tools/clang/test/CodeGenCXX/thunks-available-externally.cpp
+@@ -1,4 +1,4 @@
+-// RUN: %clang_cc1 %s -I%S -triple=x86_64-apple-darwin10 -emit-llvm -O3 -o - | FileCheck %s
++// RUN: %clang_cc1 %s -I%S -triple=x86_64-apple-darwin10 -emit-llvm-only -O3
+ 
+ // Check that we don't assert on this case.
+ namespace Test1 {
+@@ -58,15 +58,6 @@
+   b->f();
+ }
+ 
+-// CHECK: define void @_ZN5Test21fEv()
+-// CHECK: call void @_ZN5Test21C1fEv
+-// CHECK: ret void
+-// CHECK: define available_externally void @_ZThn16_N5Test21C1fEv
+-void f() {
+-  C c;
+-  f(&c);
+-}
+-
+ }
+ 
+ // Test that we don't assert.
+--- tools/clang/test/CodeGenCXX/vtable-available-externally.cpp
++++ tools/clang/test/CodeGenCXX/vtable-available-externally.cpp
+@@ -2,18 +2,10 @@
+ // RUN: FileCheck --check-prefix=CHECK-TEST1 %s < %t
+ // RUN: FileCheck --check-prefix=CHECK-TEST2 %s < %t
+ // RUN: FileCheck --check-prefix=CHECK-TEST5 %s < %t
+-// RUN: FileCheck --check-prefix=CHECK-TEST7 %s < %t
+ 
+ #include <typeinfo>
+ 
+-// Test1::A's key function (f) is not defined in this translation
+-// unit, but in order to devirtualize calls, we emit the v-table with
+-// available_externally linkage.
+-//
+-// There's no real reason to do this to the RTTI, though.
+-
+-// CHECK-TEST1: @_ZTVN5Test11AE = available_externally
+-// CHECK-TEST1: @_ZTIN5Test11AE = external constant i8*
++// CHECK-TEST1: @_ZTVN5Test11AE = external unnamed_addr constant
+ namespace Test1 {
+ 
+ struct A {
+@@ -160,13 +152,4 @@
+   void f6 ();
+ };
+ 
+-// CHECK-TEST7: define void @_ZN5Test79check_c28Ev
+-// CHECK-TEST7: call void @_ZN5Test73c282f6Ev
+-// CHECK-TEST7: ret void
+-void check_c28 () {
+-  c28 obj;
+-  c11 *ptr = &obj;
+-  ptr->f6 ();
+-}
+-
+ }
+--- tools/clang/test/CodeGenCXX/vtable-linkage.cpp
++++ tools/clang/test/CodeGenCXX/vtable-linkage.cpp
+@@ -163,7 +163,7 @@
+ // F<int> is an explicit template instantiation declaration without a
+ // key function, so its vtable should have external linkage.
+ // CHECK-9: @_ZTV1FIiE = external unnamed_addr constant
+-// CHECK-9-OPT: @_ZTV1FIiE = available_externally unnamed_addr constant
++// CHECK-9-OPT: @_ZTV1FIiE = external unnamed_addr constant
+ 
+ // E<int> is an explicit template instantiation declaration. It has a
+ // key function that is not instantiated, so we should only reference