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llvm-project/llvm/test/CodeGen/X86/global-access-pie-copyreloc...

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X86: Do not use llc -march in tests. `llc -march` is problematic because it only switches the target architecture, but leaves the operating system unchanged. This occasionally leads to indeterministic tests because the OS from LLVM_DEFAULT_TARGET_TRIPLE is used. However we can simply always use `llc -mtriple` instead. This changes all the tests to do this to avoid people using -march when they copy and paste parts of tests. See also the discussion in https://reviews.llvm.org/D35287 llvm-svn: 309774
2017-08-02 08:28:10 +08:00
; RUN: llc < %s -mcpu=generic -mtriple=x86_64-linux-gnu -relocation-model=pic -pie-copy-relocations \
New llc option pie-copy-relocations to optimize access to extern globals. This option indicates copy relocations support is available from the linker when building as PIE and allows accesses to extern globals to avoid the GOT. Differential Revision: https://reviews.llvm.org/D24849 llvm-svn: 284160
2016-10-14 04:54:39 +08:00
; RUN: | FileCheck -check-prefix=X64 %s
X86: Do not use llc -march in tests. `llc -march` is problematic because it only switches the target architecture, but leaves the operating system unchanged. This occasionally leads to indeterministic tests because the OS from LLVM_DEFAULT_TARGET_TRIPLE is used. However we can simply always use `llc -mtriple` instead. This changes all the tests to do this to avoid people using -march when they copy and paste parts of tests. See also the discussion in https://reviews.llvm.org/D35287 llvm-svn: 309774
2017-08-02 08:28:10 +08:00
; RUN: llc < %s -emulated-tls -mcpu=generic -mtriple=i386-linux-gnu -relocation-model=pic -pie-copy-relocations \
New llc option pie-copy-relocations to optimize access to extern globals. This option indicates copy relocations support is available from the linker when building as PIE and allows accesses to extern globals to avoid the GOT. Differential Revision: https://reviews.llvm.org/D24849 llvm-svn: 284160
2016-10-14 04:54:39 +08:00
; RUN: | FileCheck -check-prefix=X32 %s
; External Linkage
@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@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
@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@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
@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@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.
@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@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
}
D36604: PR34148: Do not assume we can use a copy relocation for an `external_weak` global An `external_weak` global may be intended to resolve as a null pointer if it's not defined, so it doesn't make sense to use a copy relocation for it. Differential Revision: https://reviews.llvm.org/D36604 llvm-svn: 310773
2017-08-12 07:52:28 +08:00
; ExternalWeak Linkage
@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@GOT(%eax), %eax
; X64-LABEL: my_access_global_d:
; X64: movq e@GOTPCREL(%rip), %rax
entry:
ret i32* @e
}
Handle undefined weak hidden symbols on all architectures. We were handling the non-hidden case in lib/Target/TargetMachine.cpp, but the hidden case was handled in architecture dependent code and only X86_64 and AArch64 were covered. While it is true that some code sequences in some ABIs might be able to produce the correct value at runtime, that doesn't seem to be the common case. I left the AArch64 code in place since it also forces a got access for non-pic code. It is not clear if that is needed, but it is probably better to change that in another commit. llvm-svn: 316799
2017-10-28 05:18:48 +08:00
; ExternalWeak hidden Linkage
@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@GOT(%eax), %eax
; X64-LABEL: my_access_global_he:
; X64: movq he@GOTPCREL(%rip), %rax
ret i32* @he
}
New llc option pie-copy-relocations to optimize access to extern globals. This option indicates copy relocations support is available from the linker when building as PIE and allows accesses to extern globals to avoid the GOT. Differential Revision: https://reviews.llvm.org/D24849 llvm-svn: 284160
2016-10-14 04:54:39 +08:00
; 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@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@GOT(%ebx), %eax
; X64-LABEL: my_access_fp_foo:
; X64: movq foo@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@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}