From bef2663751fd1f9ad12ddcbea2da87f47f1f42c7 Mon Sep 17 00:00:00 2001
From: Scott Linder <scott@scottlinder.com>
Date: Mon, 28 Jan 2019 17:12:19 +0000
Subject: [PATCH] Add -fapply-global-visibility-to-externs for -cc1
Introduce an option to request global visibility settings be applied to
declarations without a definition or an explicit visibility, rather than
the existing behavior of giving these default visibility. When the
visibility of all or most extern definitions are known this allows for
the same optimisations -fvisibility permits without updating source code
to annotate all declarations.
Differential Revision: https://reviews.llvm.org/D56868
llvm-svn: 352391
---
clang/include/clang/Basic/LangOptions.def | 2 +
clang/include/clang/Driver/CC1Options.td | 2 +
clang/lib/CodeGen/CodeGenModule.cpp | 6 ++-
clang/lib/Driver/ToolChains/AMDGPU.cpp | 1 +
clang/lib/Driver/ToolChains/HIP.cpp | 4 +-
clang/lib/Frontend/CompilerInvocation.cpp | 3 ++
clang/test/CodeGen/set-visibility-for-decls.c | 42 +++++++++++++++++++
clang/test/Driver/amdgpu-visibility.cl | 12 +++++-
clang/test/Driver/hip-toolchain-no-rdc.hip | 4 ++
clang/test/Driver/hip-toolchain-rdc.hip | 4 +-
10 files changed, 74 insertions(+), 6 deletions(-)
create mode 100644 clang/test/CodeGen/set-visibility-for-decls.c
diff --git a/clang/include/clang/Basic/LangOptions.def b/clang/include/clang/Basic/LangOptions.def
index 36d3764c74da..4e391d2562c4 100644
--- a/clang/include/clang/Basic/LangOptions.def
+++ b/clang/include/clang/Basic/LangOptions.def
@@ -261,6 +261,8 @@ ENUM_LANGOPT(ValueVisibilityMode, Visibility, 3, DefaultVisibility,
"default visibility for functions and variables [-fvisibility]")
ENUM_LANGOPT(TypeVisibilityMode, Visibility, 3, DefaultVisibility,
"default visibility for types [-ftype-visibility]")
+LANGOPT(SetVisibilityForExternDecls, 1, 0,
+ "apply global symbol visibility to external declarations without an explicit visibility")
ENUM_LANGOPT(StackProtector, StackProtectorMode, 2, SSPOff,
"stack protector mode")
ENUM_LANGOPT(TrivialAutoVarInit, TrivialAutoVarInitKind, 2, TrivialAutoVarInitKind::Uninitialized,
diff --git a/clang/include/clang/Driver/CC1Options.td b/clang/include/clang/Driver/CC1Options.td
index 4cce9e63c31f..cead87201eee 100644
--- a/clang/include/clang/Driver/CC1Options.td
+++ b/clang/include/clang/Driver/CC1Options.td
@@ -702,6 +702,8 @@ def fvisibility : Separate<["-"], "fvisibility">,
HelpText<"Default type and symbol visibility">;
def ftype_visibility : Separate<["-"], "ftype-visibility">,
HelpText<"Default type visibility">;
+def fapply_global_visibility_to_externs : Flag<["-"], "fapply-global-visibility-to-externs">,
+ HelpText<"Apply global symbol visibility to external declarations without an explicit visibility">;
def ftemplate_depth : Separate<["-"], "ftemplate-depth">,
HelpText<"Maximum depth of recursive template instantiation">;
def foperator_arrow_depth : Separate<["-"], "foperator-arrow-depth">,
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 0be4bad7ee7b..5a1b7cfe4fa1 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -731,9 +731,11 @@ void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV,
}
if (!D)
return;
- // Set visibility for definitions.
+ // Set visibility for definitions, and for declarations if requested globally
+ // or set explicitly.
LinkageInfo LV = D->getLinkageAndVisibility();
- if (LV.isVisibilityExplicit() || !GV->isDeclarationForLinker())
+ if (LV.isVisibilityExplicit() || getLangOpts().SetVisibilityForExternDecls ||
+ !GV->isDeclarationForLinker())
GV->setVisibility(GetLLVMVisibility(LV.getVisibility()));
}
diff --git a/clang/lib/Driver/ToolChains/AMDGPU.cpp b/clang/lib/Driver/ToolChains/AMDGPU.cpp
index a03a60733034..b9300bcc42e7 100644
--- a/clang/lib/Driver/ToolChains/AMDGPU.cpp
+++ b/clang/lib/Driver/ToolChains/AMDGPU.cpp
@@ -108,5 +108,6 @@ void AMDGPUToolChain::addClangTargetOptions(
options::OPT_fvisibility_ms_compat)) {
CC1Args.push_back("-fvisibility");
CC1Args.push_back("hidden");
+ CC1Args.push_back("-fapply-global-visibility-to-externs");
}
}
diff --git a/clang/lib/Driver/ToolChains/HIP.cpp b/clang/lib/Driver/ToolChains/HIP.cpp
index f55dd2fc04f0..cd8ed6118fe0 100644
--- a/clang/lib/Driver/ToolChains/HIP.cpp
+++ b/clang/lib/Driver/ToolChains/HIP.cpp
@@ -293,8 +293,10 @@ void HIPToolChain::addClangTargetOptions(
// Default to "hidden" visibility, as object level linking will not be
// supported for the foreseeable future.
if (!DriverArgs.hasArg(options::OPT_fvisibility_EQ,
- options::OPT_fvisibility_ms_compat))
+ options::OPT_fvisibility_ms_compat)) {
CC1Args.append({"-fvisibility", "hidden"});
+ CC1Args.push_back("-fapply-global-visibility-to-externs");
+ }
}
llvm::opt::DerivedArgList *
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 4d72924fad21..dbc29e24aee3 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -2501,6 +2501,9 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
if (Args.hasArg(OPT_fvisibility_global_new_delete_hidden))
Opts.GlobalAllocationFunctionVisibilityHidden = 1;
+ if (Args.hasArg(OPT_fapply_global_visibility_to_externs))
+ Opts.SetVisibilityForExternDecls = 1;
+
if (Args.hasArg(OPT_ftrapv)) {
Opts.setSignedOverflowBehavior(LangOptions::SOB_Trapping);
// Set the handler, if one is specified.
diff --git a/clang/test/CodeGen/set-visibility-for-decls.c b/clang/test/CodeGen/set-visibility-for-decls.c
new file mode 100644
index 000000000000..04232f871516
--- /dev/null
+++ b/clang/test/CodeGen/set-visibility-for-decls.c
@@ -0,0 +1,42 @@
+// RUN: %clang_cc1 %s -std=c11 -triple=x86_64-pc-linux -fvisibility hidden -fapply-global-visibility-to-externs -emit-llvm -o - | FileCheck --check-prefix=CHECK-HIDDEN %s
+// RUN: %clang_cc1 %s -std=c11 -triple=x86_64-pc-linux -fvisibility protected -fapply-global-visibility-to-externs -emit-llvm -o - | FileCheck --check-prefix=CHECK-PROTECTED %s
+// RUN: %clang_cc1 %s -std=c11 -triple=x86_64-pc-linux -fvisibility default -fapply-global-visibility-to-externs -emit-llvm -o - | FileCheck --check-prefix=CHECK-DEFAULT %s
+
+// CHECK-HIDDEN: @var_hidden = external hidden global
+// CHECK-PROTECTED: @var_hidden = external hidden global
+// CHECK-DEFAULT: @var_hidden = external hidden global
+__attribute__((visibility("hidden"))) extern int var_hidden;
+// CHECK-HIDDEN: @var_protected = external protected global
+// CHECK-PROTECTED: @var_protected = external protected global
+// CHECK-DEFAULT: @var_protected = external protected global
+__attribute__((visibility("protected"))) extern int var_protected;
+// CHECK-HIDDEN: @var_default = external global
+// CHECK-PROTECTED: @var_default = external global
+// CHECK-DEFAULT: @var_default = external global
+__attribute__((visibility("default"))) extern int var_default;
+// CHECK-HIDDEN: @var = external hidden global
+// CHECK-PROTECTED: @var = external protected global
+// CHECK-DEFAULT: @var = external global
+extern int var;
+
+// CHECK-HIDDEN: declare hidden i32 @func_hidden()
+// CHECK-PROTECTED: declare hidden i32 @func_hidden()
+// CHECK-DEFAULT: declare hidden i32 @func_hidden()
+__attribute__((visibility("hidden"))) int func_hidden(void);
+// CHECK-HIDDEN: declare protected i32 @func_protected()
+// CHECK-PROTECTED: declare protected i32 @func_protected()
+// CHECK-DEFAULT: declare protected i32 @func_protected()
+__attribute__((visibility("protected"))) int func_protected(void);
+// CHECK-HIDDEN: declare i32 @func_default()
+// CHECK-PROTECTED: declare i32 @func_default()
+// CHECK-DEFAULT: declare i32 @func_default()
+__attribute__((visibility("default"))) int func_default(void);
+// CHECK-HIDDEN: declare hidden i32 @func()
+// CHECK-PROTECTED: declare protected i32 @func()
+// CHECK-DEFAULT: declare i32 @func()
+int func(void);
+
+int use() {
+ return var_hidden + var_protected + var_default + var +
+ func_hidden() + func_protected() + func_default() + func();
+}
diff --git a/clang/test/Driver/amdgpu-visibility.cl b/clang/test/Driver/amdgpu-visibility.cl
index 35969db0340e..19756d4744e0 100644
--- a/clang/test/Driver/amdgpu-visibility.cl
+++ b/clang/test/Driver/amdgpu-visibility.cl
@@ -2,6 +2,14 @@
// RUN: %clang -### -target amdgcn-amd-amdhsa -x cl -c -emit-llvm -fvisibility=protected %s 2>&1 | FileCheck -check-prefix=OVERRIDE-PROTECTED %s
// RUN: %clang -### -target amdgcn-amd-amdhsa -x cl -c -emit-llvm -fvisibility-ms-compat %s 2>&1 | FileCheck -check-prefix=OVERRIDE-MS %s
-// DEFAULT: "-fvisibility" "hidden"
+// DEFAULT-DAG: "-fvisibility" "hidden"
+// DEFAULT-DAG: "-fapply-global-visibility-to-externs"
+
+// OVERRIDE-PROTECTED-NOT: "-fapply-global-visibility-to-externs"
// OVERRIDE-PROTECTED: "-fvisibility" "protected"
-// OVERRIDE-MS: "-fvisibility" "hidden" "-ftype-visibility" "default"
+// OVERRIDE-PROTECTED-NOT: "-fapply-global-visibility-to-externs"
+
+// OVERRIDE-MS-NOT: "-fapply-global-visibility-to-externs"
+// OVERRIDE-MS-DAG: "-fvisibility" "hidden"
+// OVERRIDE-MS-DAG: "-ftype-visibility" "default"
+// OVERRIDE-MS-NOT: "-fapply-global-visibility-to-externs"
diff --git a/clang/test/Driver/hip-toolchain-no-rdc.hip b/clang/test/Driver/hip-toolchain-no-rdc.hip
index 4f31a39a72b9..e8e491858f7c 100644
--- a/clang/test/Driver/hip-toolchain-no-rdc.hip
+++ b/clang/test/Driver/hip-toolchain-no-rdc.hip
@@ -20,6 +20,7 @@
// CHECK-SAME: "-aux-triple" "x86_64-unknown-linux-gnu" "-emit-llvm-bc"
// CHECK-SAME: {{.*}} "-main-file-name" "a.cu" {{.*}} "-target-cpu" "gfx803"
// CHECK-SAME: "-fcuda-is-device" "-fvisibility" "hidden"
+// CHECK-SAME: "-fapply-global-visibility-to-externs"
// CHECK-SAME: {{.*}} "-o" [[A_BC_803:".*bc"]] "-x" "hip"
// CHECK-SAME: {{.*}} [[A_SRC:".*a.cu"]]
@@ -47,6 +48,7 @@
// CHECK-SAME: "-aux-triple" "x86_64-unknown-linux-gnu" "-emit-llvm-bc"
// CHECK-SAME: {{.*}} "-main-file-name" "a.cu" {{.*}} "-target-cpu" "gfx900"
// CHECK-SAME: "-fcuda-is-device" "-fvisibility" "hidden"
+// CHECK-SAME: "-fapply-global-visibility-to-externs"
// CHECK-SAME: {{.*}} "-o" [[A_BC_900:".*bc"]] "-x" "hip"
// CHECK-SAME: {{.*}} [[A_SRC]]
@@ -89,6 +91,7 @@
// CHECK-SAME: "-aux-triple" "x86_64-unknown-linux-gnu" "-emit-llvm-bc"
// CHECK-SAME: {{.*}} "-main-file-name" "b.hip" {{.*}} "-target-cpu" "gfx803"
// CHECK-SAME: "-fcuda-is-device" "-fvisibility" "hidden"
+// CHECK-SAME: "-fapply-global-visibility-to-externs"
// CHECK-SAME: {{.*}} "-o" [[B_BC_803:".*bc"]] "-x" "hip"
// CHECK-SAME: {{.*}} [[B_SRC:".*b.hip"]]
@@ -116,6 +119,7 @@
// CHECK-SAME: "-aux-triple" "x86_64-unknown-linux-gnu" "-emit-llvm-bc"
// CHECK-SAME: {{.*}} "-main-file-name" "b.hip" {{.*}} "-target-cpu" "gfx900"
// CHECK-SAME: "-fcuda-is-device" "-fvisibility" "hidden"
+// CHECK-SAME: "-fapply-global-visibility-to-externs"
// CHECK-SAME: {{.*}} "-o" [[B_BC_900:".*bc"]] "-x" "hip"
// CHECK-SAME: {{.*}} [[B_SRC]]
diff --git a/clang/test/Driver/hip-toolchain-rdc.hip b/clang/test/Driver/hip-toolchain-rdc.hip
index 5f3fd9250b6c..dc6fc6f6518d 100644
--- a/clang/test/Driver/hip-toolchain-rdc.hip
+++ b/clang/test/Driver/hip-toolchain-rdc.hip
@@ -12,10 +12,11 @@
// RUN: %S/Inputs/hip_multiple_inputs/b.hip \
// RUN: 2>&1 | FileCheck %s
-// CHECK: [[CLANG:".*clang.*"]] "-cc1" "-triple" "amdgcn-amd-amdhsa"
+// CHECK: [[CLANG:".*clang.*"]] "-cc1" "-triple" "amdgcn-amd-amdhsa"
// CHECK-SAME: "-aux-triple" "x86_64-unknown-linux-gnu" "-emit-llvm-bc"
// CHECK-SAME: {{.*}} "-main-file-name" "a.cu" {{.*}} "-target-cpu" "gfx803"
// CHECK-SAME: "-fcuda-is-device" "-fgpu-rdc" "-fvisibility" "hidden"
+// CHECK-SAME: "-fapply-global-visibility-to-externs"
// CHECK-SAME: {{.*}} "-o" [[A_BC:".*bc"]] "-x" "hip"
// CHECK-SAME: {{.*}} [[A_SRC:".*a.cu"]]
@@ -23,6 +24,7 @@
// CHECK-SAME: "-aux-triple" "x86_64-unknown-linux-gnu" "-emit-llvm-bc"
// CHECK-SAME: {{.*}} "-main-file-name" "b.hip" {{.*}} "-target-cpu" "gfx803"
// CHECK-SAME: "-fcuda-is-device" "-fgpu-rdc" "-fvisibility" "hidden"
+// CHECK-SAME: "-fapply-global-visibility-to-externs"
// CHECK-SAME: {{.*}} "-o" [[B_BC:".*bc"]] "-x" "hip"
// CHECK-SAME: {{.*}} [[B_SRC:".*b.hip"]]