[llvm-branch-commits] [clang] e42021d - [Clang][-fvisibility-from-dllstorageclass] Set DSO Locality from final visibility
Ben Dunbobbin via llvm-branch-commits
llvm-branch-commits at lists.llvm.org
Tue Nov 24 15:40:26 PST 2020
Author: Ben Dunbobbin
Date: 2020-11-24T00:32:14Z
New Revision: e42021d5cc25a8dc7e3efac1e7007cc0c1a7b2bd
URL: https://github.com/llvm/llvm-project/commit/e42021d5cc25a8dc7e3efac1e7007cc0c1a7b2bd
DIFF: https://github.com/llvm/llvm-project/commit/e42021d5cc25a8dc7e3efac1e7007cc0c1a7b2bd.diff
LOG: [Clang][-fvisibility-from-dllstorageclass] Set DSO Locality from final visibility
Ensure that the DSO Locality of the globals in the IR is derived from
their final visibility when using -fvisibility-from-dllstorageclass.
To accomplish this we reset the DSO locality of globals (before
setting their visibility from their dllstorageclass) at the end of
IRGen in Clang. This removes any effects that visibility options or
annotations may have had on the DSO locality.
The resulting DSO locality of the globals will be pessimistic
w.r.t. to the normal compiler IRGen.
Differential Revision: https://reviews.llvm.org/D91779
Added:
Modified:
clang/lib/CodeGen/CodeGenModule.cpp
clang/test/CodeGenCXX/visibility-dllstorageclass.cpp
Removed:
################################################################################
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index f56b7374082f..6d0228e9e2e9 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -420,6 +420,13 @@ static void setVisibilityFromDLLStorageClass(const clang::LangOptions &LO,
if (GV.hasAppendingLinkage() || GV.hasLocalLinkage())
continue;
+ // Reset DSO locality before setting the visibility. This removes
+ // any effects that visibility options and annotations may have
+ // had on the DSO locality. Setting the visibility will implicitly set
+ // appropriate globals to DSO Local; however, this will be pessimistic
+ // w.r.t. to the normal compiler IRGen.
+ GV.setDSOLocal(false);
+
if (GV.isDeclarationForLinker()) {
GV.setVisibility(GV.getDLLStorageClass() ==
llvm::GlobalValue::DLLImportStorageClass
diff --git a/clang/test/CodeGenCXX/visibility-dllstorageclass.cpp b/clang/test/CodeGenCXX/visibility-dllstorageclass.cpp
index 9003909f3ee0..c4dddcec2eb0 100644
--- a/clang/test/CodeGenCXX/visibility-dllstorageclass.cpp
+++ b/clang/test/CodeGenCXX/visibility-dllstorageclass.cpp
@@ -5,12 +5,14 @@
// RUN: %clang_cc1 -triple x86_64-unknown-windows-itanium -fdeclspec \
// RUN: -fvisibility hidden \
+// RUN: -fapply-global-visibility-to-externs \
// RUN: -fvisibility-from-dllstorageclass \
// RUN: -x c++ %s -S -emit-llvm -o - | \
-// RUN: FileCheck %s --check-prefixes=DEFAULT
+// RUN: FileCheck %s --check-prefixes=DEFAULTS
// RUN: %clang_cc1 -triple x86_64-unknown-windows-itanium -fdeclspec \
// RUN: -fvisibility hidden \
+// RUN: -fapply-global-visibility-to-externs \
// RUN: -fvisibility-from-dllstorageclass \
// RUN: -fvisibility-dllexport=hidden \
// RUN: -fvisibility-nodllstorageclass=protected \
@@ -19,45 +21,78 @@
// RUN: -x c++ %s -S -emit-llvm -o - | \
// RUN: FileCheck %s --check-prefixes=EXPLICIT
+// RUN: %clang_cc1 -triple x86_64-unknown-windows-itanium -fdeclspec \
+// RUN: -fvisibility hidden \
+// RUN: -fapply-global-visibility-to-externs \
+// RUN: -fvisibility-from-dllstorageclass \
+// RUN: -fvisibility-dllexport=default \
+// RUN: -fvisibility-nodllstorageclass=default \
+// RUN: -fvisibility-externs-dllimport=default \
+// RUN: -fvisibility-externs-nodllstorageclass=default \
+// RUN: -x c++ %s -S -emit-llvm -o - | \
+// RUN: FileCheck %s --check-prefixes=ALL_DEFAULT
+
// Local
static void l() {}
void use_locals(){l();}
-// DEFAULT-DAG: define internal void @_ZL1lv()
+// DEFAULTS-DAG: define internal void @_ZL1lv()
// EXPLICIT-DAG: define internal void @_ZL1lv()
+// ALL_DEFAULT-DAG: define internal void @_ZL1lv()
// Function
void f() {}
void __declspec(dllexport) exported_f() {}
-// DEFAULT-DAG: define hidden void @_Z1fv()
-// DEFAULT-DAG: define dso_local void @_Z10exported_fv()
+// DEFAULTS-DAG: define hidden void @_Z1fv()
+// DEFAULTS-DAG: define void @_Z10exported_fv()
// EXPLICIT-DAG: define protected void @_Z1fv()
// EXPLICIT-DAG: define hidden void @_Z10exported_fv()
+// ALL_DEFAULT-DAG: define void @_Z1fv()
+// ALL_DEFAULT-DAG: define void @_Z10exported_fv()
// Variable
int d = 123;
__declspec(dllexport) int exported_d = 123;
-// DEFAULT-DAG: @d = hidden global
-// DEFAULT-DAG: @exported_d = dso_local global
+// DEFAULTS-DAG: @d = hidden global
+// DEFAULTS-DAG: @exported_d = global
// EXPLICIT-DAG: @d = protected global
// EXPLICIT-DAG: @exported_d = hidden global
+// ALL_DEFAULT-DAG: @d = global
+// ALL_DEFAULT-DAG: @exported_d = global
// Alias
extern "C" void aliased() {}
void a() __attribute__((alias("aliased")));
void __declspec(dllexport) a_exported() __attribute__((alias("aliased")));
-// DEFAULT-DAG: @_Z1av = hidden alias
-// DEFAULT-DAG: @_Z10a_exportedv = dso_local alias
+// DEFAULTS-DAG: @_Z1av = hidden alias
+// DEFAULTS-DAG: @_Z10a_exportedv = alias
// EXPLICIT-DAG: @_Z1av = protected alias
// EXPLICIT-DAG: @_Z10a_exportedv = hidden alias
+// ALL_DEFAULT-DAG: @_Z1av = alias
+// ALL_DEFAULT-DAG: @_Z10a_exportedv = alias
// Declaration
extern void e();
extern void __declspec(dllimport) imported_e();
-void use_declarations(){e(); imported_e();}
-// DEFAULT-DAG: declare hidden void @_Z1ev()
-// DEFAULT-DAG: declare void @_Z10imported_ev()
+// DEFAULTS-DAG: declare hidden void @_Z1ev()
+// DEFAULTS-DAG: declare void @_Z10imported_ev()
// EXPLICIT-DAG: declare protected void @_Z1ev()
// EXPLICIT-DAG: declare hidden void @_Z10imported_ev()
+// ALL_DEFAULT-DAG: declare void @_Z1ev()
+// ALL_DEFAULT-DAG: declare void @_Z10imported_ev()
+
+// Weak Declaration
+__attribute__((weak))
+extern void w();
+__attribute__((weak))
+extern void __declspec(dllimport) imported_w();
+// DEFAULTS-DAG: declare extern_weak hidden void @_Z1wv()
+// DEFAULTS-DAG: declare extern_weak void @_Z10imported_wv()
+// EXPLICIT-DAG: declare extern_weak protected void @_Z1wv()
+// EXPLICIT-DAG: declare extern_weak hidden void @_Z10imported_wv()
+// ALL_DEFAULT-DAG: declare extern_weak void @_Z1wv()
+// ALL_DEFAULT-DAG: declare extern_weak void @_Z10imported_wv()
+
+void use_declarations(){e(); imported_e(); w(); imported_w();}
// Show that -fvisibility-from-dllstorageclass overrides the effect of visibility annotations.
@@ -65,12 +100,12 @@ struct __attribute__((type_visibility("protected"))) t {
virtual void foo();
};
void t::foo() {}
-// DEFAULT-DAG: @_ZTV1t = hidden unnamed_addr constant
+// DEFAULTS-DAG: @_ZTV1t = hidden unnamed_addr constant
int v __attribute__ ((__visibility__ ("protected"))) = 123;
-// DEFAULT-DAG: @v = hidden global
+// DEFAULTS-DAG: @v = hidden global
#pragma GCC visibility push(protected)
int p = 345;
#pragma GCC visibility pop
-// DEFAULT-DAG: @p = hidden global
+// DEFAULTS-DAG: @p = hidden global
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