llvm-6502/test/CodeGen/AArch64/arm64-tls-dynamics.ll
Kristof Beyls 78c4ef5120 Fix PR22408 - LLVM producing AArch64 TLS relocations that GNU linkers cannot handle yet.
As is described at http://llvm.org/bugs/show_bug.cgi?id=22408, the GNU linkers
ld.bfd and ld.gold currently only support a subset of the whole range of AArch64
ELF TLS relocations. Furthermore, they assume that some of the code sequences to
access thread-local variables are produced in a very specific sequence.
When the sequence is not as the linker expects, it can silently mis-relaxe/mis-optimize
the instructions.
Even if that wouldn't be the case, it's good to produce the exact sequence,
as that ensures that linkers can perform optimizing relaxations.

This patch:

* implements support for 16MiB TLS area size instead of 4GiB TLS area size. Ideally clang
  would grow an -mtls-size option to allow support for both, but that's not part of this patch.
* by default doesn't produce local dynamic access patterns, as even modern ld.bfd and ld.gold
  linkers do not support the associated relocations. An option (-aarch64-elf-ldtls-generation)
  is added to enable generation of local dynamic code sequence, but is off by default.
* makes sure that the exact expected code sequence for local dynamic and general dynamic
  accesses is produced, by making use of a new pseudo instruction. The patch also removes
  two (AArch64ISD::TLSDESC_BLR, AArch64ISD::TLSDESC_CALL) pre-existing AArch64-specific pseudo
  SDNode instructions that are superseded by the new one (TLSDESC_CALLSEQ).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231227 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-04 09:12:08 +00:00

170 lines
6.6 KiB
LLVM

; RUN: llc -mtriple=arm64-none-linux-gnu -relocation-model=pic -aarch64-elf-ldtls-generation=1 -verify-machineinstrs < %s | FileCheck %s
; RUN: llc -mtriple=arm64-none-linux-gnu -relocation-model=pic -aarch64-elf-ldtls-generation=1 -filetype=obj < %s | llvm-objdump -r - | FileCheck --check-prefix=CHECK-RELOC %s
; RUN: llc -mtriple=arm64-none-linux-gnu -relocation-model=pic -verify-machineinstrs < %s | FileCheck --check-prefix=CHECK-NOLD %s
; RUN: llc -mtriple=arm64-none-linux-gnu -relocation-model=pic -filetype=obj < %s | llvm-objdump -r - | FileCheck --check-prefix=CHECK-NOLD-RELOC %s
@general_dynamic_var = external thread_local global i32
define i32 @test_generaldynamic() {
; CHECK-LABEL: test_generaldynamic:
%val = load i32, i32* @general_dynamic_var
ret i32 %val
; CHECK: adrp x[[TLSDESC_HI:[0-9]+]], :tlsdesc:general_dynamic_var
; CHECK-NEXT: ldr [[CALLEE:x[0-9]+]], [x[[TLSDESC_HI]], :tlsdesc_lo12:general_dynamic_var]
; CHECK-NEXT: add x0, x[[TLSDESC_HI]], :tlsdesc_lo12:general_dynamic_var
; CHECK-NEXT: .tlsdesccall general_dynamic_var
; CHECK-NEXT: blr [[CALLEE]]
; CHECK-NOLD: adrp x[[TLSDESC_HI:[0-9]+]], :tlsdesc:general_dynamic_var
; CHECK-NOLD-NEXT: ldr [[CALLEE:x[0-9]+]], [x[[TLSDESC_HI]], :tlsdesc_lo12:general_dynamic_var]
; CHECK-NOLD-NEXT: add x0, x[[TLSDESC_HI]], :tlsdesc_lo12:general_dynamic_var
; CHECK-NOLD-NEXT: .tlsdesccall general_dynamic_var
; CHECK-NOLD-NEXT: blr [[CALLEE]]
; CHECK: mrs x[[TP:[0-9]+]], TPIDR_EL0
; CHECK: ldr w0, [x[[TP]], x0]
; CHECK-NOLD: mrs x[[TP:[0-9]+]], TPIDR_EL0
; CHECK-NOLD: ldr w0, [x[[TP]], x0]
; CHECK-RELOC: R_AARCH64_TLSDESC_ADR_PAGE21
; CHECK-RELOC: R_AARCH64_TLSDESC_LD64_LO12_NC
; CHECK-RELOC: R_AARCH64_TLSDESC_ADD_LO12_NC
; CHECK-RELOC: R_AARCH64_TLSDESC_CALL
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_ADR_PAGE21
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_LD64_LO12_NC
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_ADD_LO12_NC
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_CALL
}
define i32* @test_generaldynamic_addr() {
; CHECK-LABEL: test_generaldynamic_addr:
ret i32* @general_dynamic_var
; CHECK: adrp x[[TLSDESC_HI:[0-9]+]], :tlsdesc:general_dynamic_var
; CHECK-NEXT: ldr [[CALLEE:x[0-9]+]], [x[[TLSDESC_HI]], :tlsdesc_lo12:general_dynamic_var]
; CHECK-NEXT: add x0, x[[TLSDESC_HI]], :tlsdesc_lo12:general_dynamic_var
; CHECK-NEXT: .tlsdesccall general_dynamic_var
; CHECK-NEXT: blr [[CALLEE]]
; CHECK: mrs [[TP:x[0-9]+]], TPIDR_EL0
; CHECK: add x0, [[TP]], x0
; CHECK-RELOC: R_AARCH64_TLSDESC_ADR_PAGE21
; CHECK-RELOC: R_AARCH64_TLSDESC_LD64_LO12_NC
; CHECK-RELOC: R_AARCH64_TLSDESC_ADD_LO12_NC
; CHECK-RELOC: R_AARCH64_TLSDESC_CALL
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_ADR_PAGE21
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_LD64_LO12_NC
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_ADD_LO12_NC
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_CALL
}
@local_dynamic_var = external thread_local(localdynamic) global i32
define i32 @test_localdynamic() {
; CHECK-LABEL: test_localdynamic:
%val = load i32, i32* @local_dynamic_var
ret i32 %val
; CHECK: adrp x[[TLSDESC_HI:[0-9]+]], :tlsdesc:_TLS_MODULE_BASE_
; CHECK-NEXT: ldr [[CALLEE:x[0-9]+]], [x[[TLSDESC_HI]], :tlsdesc_lo12:_TLS_MODULE_BASE_]
; CHECK-NEXT: add x0, x[[TLSDESC_HI]], :tlsdesc_lo12:_TLS_MODULE_BASE_
; CHECK-NEXT: .tlsdesccall _TLS_MODULE_BASE_
; CHECK-NEXT: blr [[CALLEE]]
; CHECK-NEXT: add x[[TPOFF:[0-9]+]], x0, :dtprel_hi12:local_dynamic_var
; CHECK-NEXT: add x[[TPOFF]], x[[TPOFF]], :dtprel_lo12_nc:local_dynamic_var
; CHECK: mrs x[[TPIDR:[0-9]+]], TPIDR_EL0
; CHECK: ldr w0, [x[[TPIDR]], x[[TPOFF]]]
; CHECK-NOLD: adrp x[[TLSDESC_HI:[0-9]+]], :tlsdesc:local_dynamic_var
; CHECK-NOLD-NEXT: ldr [[CALLEE:x[0-9]+]], [x[[TLSDESC_HI]], :tlsdesc_lo12:local_dynamic_var]
; CHECK-NOLD-NEXT: add x0, x[[TLSDESC_HI]], :tlsdesc_lo12:local_dynamic_var
; CHECK-NOLD-NEXT: .tlsdesccall local_dynamic_var
; CHECK-NOLD-NEXT: blr [[CALLEE]]
; CHECK-NOLD: mrs x[[TPIDR:[0-9]+]], TPIDR_EL0
; CHECK-NOLD: ldr w0, [x[[TPIDR]], x0]
; CHECK-RELOC: R_AARCH64_TLSDESC_ADR_PAGE21
; CHECK-RELOC: R_AARCH64_TLSDESC_LD64_LO12_NC
; CHECK-RELOC: R_AARCH64_TLSDESC_ADD_LO12_NC
; CHECK-RELOC: R_AARCH64_TLSDESC_CALL
; CHECK-RELOC: R_AARCH64_TLSLD_ADD_DTPREL_HI12
; CHECK-RELOC: R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_ADR_PAGE21
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_LD64_LO12_NC
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_ADD_LO12_NC
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_CALL
}
define i32* @test_localdynamic_addr() {
; CHECK-LABEL: test_localdynamic_addr:
; CHECK: adrp x[[TLSDESC_HI:[0-9]+]], :tlsdesc:_TLS_MODULE_BASE_
; CHECK-NEXT: ldr [[CALLEE:x[0-9]+]], [x[[TLSDESC_HI]], :tlsdesc_lo12:_TLS_MODULE_BASE_]
; CHECK-NEXT: add x0, x[[TLSDESC_HI]], :tlsdesc_lo12:_TLS_MODULE_BASE_
; CHECK-NEXT: .tlsdesccall _TLS_MODULE_BASE_
; CHECK-NEXT: blr [[CALLEE]]
; CHECK-NEXT: add x[[TPOFF:[0-9]+]], x0, :dtprel_hi12:local_dynamic_var
; CHECK-NEXT: add x[[TPOFF]], x[[TPOFF]], :dtprel_lo12_nc:local_dynamic_var
; CHECK: mrs x[[TPIDR:[0-9]+]], TPIDR_EL0
; CHECK: add x0, x[[TPIDR]], x[[TPOFF]]
; CHECK-NOLD: adrp x[[TLSDESC_HI:[0-9]+]], :tlsdesc:local_dynamic_var
; CHECK-NOLD-NEXT: ldr [[CALLEE:x[0-9]+]], [x[[TLSDESC_HI]], :tlsdesc_lo12:local_dynamic_var]
; CHECK-NOLD-NEXT: add x0, x[[TLSDESC_HI]], :tlsdesc_lo12:local_dynamic_var
; CHECK-NOLD-NEXT: .tlsdesccall local_dynamic_var
; CHECK-NOLD-NEXT: blr [[CALLEE]]
; CHECK-NOLD: mrs x[[TPIDR:[0-9]+]], TPIDR_EL0
; CHECK-NOLD: add x0, x[[TPIDR]], x0
ret i32* @local_dynamic_var
; CHECK-RELOC: R_AARCH64_TLSDESC_ADR_PAGE21
; CHECK-RELOC: R_AARCH64_TLSDESC_LD64_LO12_NC
; CHECK-RELOC: R_AARCH64_TLSDESC_ADD_LO12_NC
; CHECK-RELOC: R_AARCH64_TLSDESC_CALL
; CHECK-RELOC: R_AARCH64_TLSLD_ADD_DTPREL_HI12
; CHECK-RELOC: R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_ADR_PAGE21
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_LD64_LO12_NC
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_ADD_LO12_NC
; CHECK-NOLD-RELOC: R_AARCH64_TLSDESC_CALL
}
; The entire point of the local-dynamic access model is to have a single call to
; the expensive resolver. Make sure we achieve that goal.
@local_dynamic_var2 = external thread_local(localdynamic) global i32
define i32 @test_localdynamic_deduplicate() {
; CHECK-LABEL: test_localdynamic_deduplicate:
%val = load i32, i32* @local_dynamic_var
%val2 = load i32, i32* @local_dynamic_var2
%sum = add i32 %val, %val2
ret i32 %sum
; CHECK: adrp x[[DTPREL_HI:[0-9]+]], :tlsdesc:_TLS_MODULE_BASE_
; CHECK-NEXT: ldr [[CALLEE:x[0-9]+]], [x[[DTPREL_HI]], :tlsdesc_lo12:_TLS_MODULE_BASE_]
; CHECK-NEXT: add x0, x[[TLSDESC_HI]], :tlsdesc_lo12:_TLS_MODULE_BASE
; CHECK-NEXT: .tlsdesccall _TLS_MODULE_BASE_
; CHECK-NEXT: blr [[CALLEE]]
; CHECK-NOT: _TLS_MODULE_BASE_
; CHECK: ret
}