[clang] d2bb8c1 - [MC][TargetMachine] Delete MCTargetOptions::MCPIECopyRelocations
Fangrui Song via cfe-commits
cfe-commits at lists.llvm.org
Wed Jan 1 00:50:50 PST 2020
Author: Fangrui Song
Date: 2020-01-01T00:50:18-08:00
New Revision: d2bb8c16e711602481c8b33d0e2ccc9994eb6641
URL: https://github.com/llvm/llvm-project/commit/d2bb8c16e711602481c8b33d0e2ccc9994eb6641
DIFF: https://github.com/llvm/llvm-project/commit/d2bb8c16e711602481c8b33d0e2ccc9994eb6641.diff
LOG: [MC][TargetMachine] Delete MCTargetOptions::MCPIECopyRelocations
clang/lib/CodeGen/CodeGenModule performs the -mpie-copy-relocations
check and sets dso_local on applicable global variables. We don't need
to duplicate the work in TargetMachine shouldAssumeDSOLocal.
Verified that -mpie-copy-relocations can still emit PC relative
relocations for external variable accesses.
clang -target x86_64 -fpie -mpie-copy-relocations -c => R_X86_64_PC32
clang -target aarch64 -fpie -mpie-copy-relocations -c => R_AARCH64_ADR_PREL_PG_HI21+R_AARCH64_LDST64_ABS_LO12_NC
Added:
Modified:
clang/lib/CodeGen/BackendUtil.cpp
llvm/include/llvm/MC/MCTargetOptions.h
llvm/include/llvm/MC/MCTargetOptionsCommandFlags.inc
llvm/lib/MC/MCTargetOptions.cpp
llvm/lib/Target/TargetMachine.cpp
Removed:
llvm/test/CodeGen/X86/global-access-pie-copyrelocs.ll
################################################################################
diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index 9b1e91788346..645ef0165a53 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -485,7 +485,6 @@ static void initTargetOptions(llvm::TargetOptions &Options,
Options.MCOptions.MCNoExecStack = CodeGenOpts.NoExecStack;
Options.MCOptions.MCIncrementalLinkerCompatible =
CodeGenOpts.IncrementalLinkerCompatible;
- Options.MCOptions.MCPIECopyRelocations = CodeGenOpts.PIECopyRelocations;
Options.MCOptions.MCFatalWarnings = CodeGenOpts.FatalWarnings;
Options.MCOptions.MCNoWarn = CodeGenOpts.NoWarn;
Options.MCOptions.AsmVerbose = CodeGenOpts.AsmVerbose;
diff --git a/llvm/include/llvm/MC/MCTargetOptions.h b/llvm/include/llvm/MC/MCTargetOptions.h
index f184620ff047..51a5fc9aa26a 100644
--- a/llvm/include/llvm/MC/MCTargetOptions.h
+++ b/llvm/include/llvm/MC/MCTargetOptions.h
@@ -46,7 +46,6 @@ class MCTargetOptions {
bool MCSaveTempLabels : 1;
bool MCUseDwarfDirectory : 1;
bool MCIncrementalLinkerCompatible : 1;
- bool MCPIECopyRelocations : 1;
bool ShowMCEncoding : 1;
bool ShowMCInst : 1;
bool AsmVerbose : 1;
diff --git a/llvm/include/llvm/MC/MCTargetOptionsCommandFlags.inc b/llvm/include/llvm/MC/MCTargetOptionsCommandFlags.inc
index 9f1177f470b9..93e21b626eac 100644
--- a/llvm/include/llvm/MC/MCTargetOptionsCommandFlags.inc
+++ b/llvm/include/llvm/MC/MCTargetOptionsCommandFlags.inc
@@ -28,8 +28,6 @@ static cl::opt<bool> IncrementalLinkerCompatible(
"When used with filetype=obj, "
"emit an object file which can be used with an incremental linker"));
-static cl::opt<bool> PIECopyRelocations("pie-copy-relocations", cl::desc("PIE Copy Relocations"));
-
static cl::opt<int> DwarfVersion("dwarf-version", cl::desc("Dwarf version"),
cl::init(0));
@@ -55,7 +53,6 @@ static MCTargetOptions InitMCTargetOptionsFromFlags() {
MCTargetOptions Options;
Options.MCRelaxAll = RelaxAll;
Options.MCIncrementalLinkerCompatible = IncrementalLinkerCompatible;
- Options.MCPIECopyRelocations = PIECopyRelocations;
Options.DwarfVersion = DwarfVersion;
Options.ShowMCInst = ShowMCInst;
Options.ABIName = ABIName;
diff --git a/llvm/lib/MC/MCTargetOptions.cpp b/llvm/lib/MC/MCTargetOptions.cpp
index 96bb094134fe..5848e3ecadbe 100644
--- a/llvm/lib/MC/MCTargetOptions.cpp
+++ b/llvm/lib/MC/MCTargetOptions.cpp
@@ -15,8 +15,8 @@ MCTargetOptions::MCTargetOptions()
: MCRelaxAll(false), MCNoExecStack(false), MCFatalWarnings(false),
MCNoWarn(false), MCNoDeprecatedWarn(false), MCSaveTempLabels(false),
MCUseDwarfDirectory(false), MCIncrementalLinkerCompatible(false),
- MCPIECopyRelocations(false), ShowMCEncoding(false), ShowMCInst(false),
- AsmVerbose(false), PreserveAsmComments(true) {}
+ ShowMCEncoding(false), ShowMCInst(false), AsmVerbose(false),
+ PreserveAsmComments(true) {}
StringRef MCTargetOptions::getABIName() const {
return ABIName;
diff --git a/llvm/lib/Target/TargetMachine.cpp b/llvm/lib/Target/TargetMachine.cpp
index 519918405066..97a1eb2f190a 100644
--- a/llvm/lib/Target/TargetMachine.cpp
+++ b/llvm/lib/Target/TargetMachine.cpp
@@ -184,15 +184,14 @@ bool TargetMachine::shouldAssumeDSOLocal(const Module &M,
const Function *F = dyn_cast_or_null<Function>(GV);
if (F && F->hasFnAttribute(Attribute::NonLazyBind))
return false;
-
- bool IsTLS = GV && GV->isThreadLocal();
- bool IsAccessViaCopyRelocs =
- GV && Options.MCOptions.MCPIECopyRelocations && isa<GlobalVariable>(GV);
Triple::ArchType Arch = TT.getArch();
- bool IsPPC =
- Arch == Triple::ppc || Arch == Triple::ppc64 || Arch == Triple::ppc64le;
- // Check if we can use copy relocations. PowerPC has no copy relocations.
- if (!IsTLS && !IsPPC && (RM == Reloc::Static || IsAccessViaCopyRelocs))
+
+ // PowerPC prefers avoiding copy relocations.
+ if (Arch == Triple::ppc || TT.isPPC64())
+ return false;
+
+ // Check if we can use copy relocations.
+ if (!(GV && GV->isThreadLocal()) && RM == Reloc::Static)
return true;
}
diff --git a/llvm/test/CodeGen/X86/global-access-pie-copyrelocs.ll b/llvm/test/CodeGen/X86/global-access-pie-copyrelocs.ll
deleted file mode 100644
index 3cd75c791a64..000000000000
--- a/llvm/test/CodeGen/X86/global-access-pie-copyrelocs.ll
+++ /dev/null
@@ -1,151 +0,0 @@
-; RUN: llc < %s -emulated-tls -mcpu=generic -mtriple=x86_64-linux-gnu -relocation-model=pic -pie-copy-relocations \
-; RUN: | FileCheck -check-prefix=X64 %s
-; RUN: llc < %s -emulated-tls -mcpu=generic -mtriple=i386-linux-gnu -relocation-model=pic -pie-copy-relocations \
-; RUN: | FileCheck -check-prefix=X32 %s
-
-; RUN: llc < %s -mcpu=generic -mtriple=x86_64-linux-gnu -relocation-model=pic -pie-copy-relocations \
-; RUN: | FileCheck -check-prefix=X64 %s
-; RUN: llc < %s -mcpu=generic -mtriple=i386-linux-gnu -relocation-model=pic -pie-copy-relocations \
-; RUN: | FileCheck -check-prefix=X32 %s
-
-; External Linkage
- at a = global i32 0, align 4
-
-define i32 @my_access_global_a() #0 {
-; X32-LABEL: my_access_global_a:
-; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %eax
-; X32-NEXT: movl a at GOTOFF(%eax), %eax
-; X64-LABEL: my_access_global_a:
-; X64: movl a(%rip), %eax
-
-entry:
- %0 = load i32, i32* @a, align 4
- ret i32 %0
-}
-
-; WeakAny Linkage
- at b = weak global i32 0, align 4
-
-define i32 @my_access_global_b() #0 {
-; X32-LABEL: my_access_global_b:
-; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %eax
-; X32-NEXT: movl b at GOTOFF(%eax), %eax
-; X64-LABEL: my_access_global_b:
-; X64: movl b(%rip), %eax
-
-entry:
- %0 = load i32, i32* @b, align 4
- ret i32 %0
-}
-
-; Internal Linkage
- at c = internal global i32 0, align 4
-
-define i32 @my_access_global_c() #0 {
-; X32-LABEL: my_access_global_c:
-; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %eax
-; X32-NEXT: movl c at GOTOFF(%eax), %eax
-; X64-LABEL: my_access_global_c:
-; X64: movl c(%rip), %eax
-
-entry:
- %0 = load i32, i32* @c, align 4
- ret i32 %0
-}
-
-; External Linkage, only declaration.
- at d = external global i32, align 4
-
-define i32 @my_access_global_load_d() #0 {
-; X32-LABEL: my_access_global_load_d:
-; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %eax
-; X32-NEXT: movl d at GOTOFF(%eax), %eax
-; X64-LABEL: my_access_global_load_d:
-; X64: movl d(%rip), %eax
-
-entry:
- %0 = load i32, i32* @d, align 4
- ret i32 %0
-}
-
-; ExternalWeak Linkage
- at e = extern_weak global i32, align 4
-
-define i32* @my_access_global_d() #0 {
-; X32-LABEL: my_access_global_d:
-; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %eax
-; X32: movl e at GOT(%eax), %eax
-; X64-LABEL: my_access_global_d:
-; X64: movq e at GOTPCREL(%rip), %rax
-
-entry:
- ret i32* @e
-}
-
-; ExternalWeak hidden Linkage
- at he = extern_weak hidden global i32, align 4
-
-define i32* @my_access_global_he() #0 {
-; X32-LABEL: my_access_global_he:
-; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %eax
-; X32: movl he at GOT(%eax), %eax
-; X64-LABEL: my_access_global_he:
-; X64: movq he at GOTPCREL(%rip), %rax
- ret i32* @he
-}
-
-
-; External Linkage, only declaration, store a value.
-
-define i32 @my_access_global_store_d() #0 {
-; X32-LABEL: my_access_global_store_d:
-; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %eax
-; X32-NEXT: movl $2, d at GOTOFF(%eax)
-; X64-LABEL: my_access_global_store_d:
-; X64: movl $2, d(%rip)
-
-entry:
- store i32 2, i32* @d, align 4
- ret i32 0
-}
-
-; External Linkage, function pointer access.
-declare i32 @access_fp(i32 ()*)
-declare i32 @foo()
-
-define i32 @my_access_fp_foo() #0 {
-; X32-LABEL: my_access_fp_foo:
-; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %ebx
-; X32-NEXT: movl foo at GOT(%ebx), %eax
-; X64-LABEL: my_access_fp_foo:
-; X64: movq foo at GOTPCREL(%rip), %rdi
-
-entry:
- %call = call i32 @access_fp(i32 ()* @foo)
- ret i32 %call
-}
-
-; LinkOnceODR Linkage, function pointer access.
-
-$bar = comdat any
-
-define linkonce_odr i32 @bar() comdat {
-entry:
- ret i32 0
-}
-
-define i32 @my_access_fp_bar() #0 {
-; X32-LABEL: my_access_fp_bar:
-; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %ebx
-; X32-NEXT: leal bar at GOTOFF(%ebx), %eax
-; X64-LABEL: my_access_fp_bar:
-; X64: leaq bar(%rip), %rdi
-
-entry:
- %call = call i32 @access_fp(i32 ()* @bar)
- ret i32 %call
-}
-
-!llvm.module.flags = !{!0, !1}
-!0 = !{i32 1, !"PIC Level", i32 1}
-!1 = !{i32 1, !"PIE Level", i32 1}
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