llvm-6502/test/CodeGen/AArch64/extern-weak.ll
Asiri Rathnayake 3babc141b2 [AArch 64] Use a constant pool load for weak symbol references when
using static relocation model and small code model.

Summary: currently we generate GOT based relocations for weak symbol
references regardless of the underlying relocation model. This should
be change so that in static relocation model we use a constant pool
load instead.

Patch from: Keith Walker

Reviewers: Renato Golin, Tim Northover

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217503 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-10 13:54:38 +00:00

72 lines
2.3 KiB
LLVM

; RUN: llc -mtriple=aarch64-none-linux-gnu -relocation-model=pic -o - %s | FileCheck %s
; RUN: llc -mtriple=aarch64-none-linux-gnu -relocation-model=static -o - < %s | FileCheck --check-prefix=CHECK-STATIC %s
; RUN: llc -mtriple=aarch64-none-linux-gnu -code-model=large -o - %s | FileCheck --check-prefix=CHECK-LARGE %s
declare extern_weak i32 @var()
define i32()* @foo() {
; The usual ADRP/ADD pair can't be used for a weak reference because it must
; evaluate to 0 if the symbol is undefined. We use a GOT entry for PIC
; otherwise a litpool entry.
ret i32()* @var
; CHECK: adrp x[[ADDRHI:[0-9]+]], :got:var
; CHECK: ldr x0, [x[[ADDRHI]], :got_lo12:var]
; CHECK-STATIC: .LCPI0_0:
; CHECK-STATIC-NEXT: .xword var
; CHECK-STATIC: adrp x[[VAR:[0-9]+]], .LCPI0_0
; CHECK-STATIC: ldr x0, [x[[VAR]], :lo12:.LCPI0_0]
; In the large model, the usual relocations are absolute and can
; materialise 0.
; CHECK-LARGE: movz x0, #:abs_g3:var
; CHECK-LARGE: movk x0, #:abs_g2_nc:var
; CHECK-LARGE: movk x0, #:abs_g1_nc:var
; CHECK-LARGE: movk x0, #:abs_g0_nc:var
}
@arr_var = extern_weak global [10 x i32]
define i32* @bar() {
%addr = getelementptr [10 x i32]* @arr_var, i32 0, i32 5
; CHECK: adrp x[[ADDRHI:[0-9]+]], :got:arr_var
; CHECK: ldr [[BASE:x[0-9]+]], [x[[ADDRHI]], :got_lo12:arr_var]
; CHECK: add x0, [[BASE]], #20
; CHECK-STATIC: .LCPI1_0:
; CHECK-STATIC-NEXT: .xword arr_var
; CHECK-STATIC: ldr [[BASE:x[0-9]+]], [{{x[0-9]+}}, :lo12:.LCPI1_0]
; CHECK-STATIC: add x0, [[BASE]], #20
ret i32* %addr
; In the large model, the usual relocations are absolute and can
; materialise 0.
; CHECK-LARGE: movz [[ADDR:x[0-9]+]], #:abs_g3:arr_var
; CHECK-LARGE: movk [[ADDR]], #:abs_g2_nc:arr_var
; CHECK-LARGE: movk [[ADDR]], #:abs_g1_nc:arr_var
; CHECK-LARGE: movk [[ADDR]], #:abs_g0_nc:arr_var
}
@defined_weak_var = internal unnamed_addr global i32 0
define i32* @wibble() {
ret i32* @defined_weak_var
; CHECK: adrp [[BASE:x[0-9]+]], defined_weak_var
; CHECK: add x0, [[BASE]], :lo12:defined_weak_var
; CHECK-STATIC: adrp [[BASE:x[0-9]+]], defined_weak_var
; CHECK-STATIC: add x0, [[BASE]], :lo12:defined_weak_var
; CHECK-LARGE: movz x0, #:abs_g3:defined_weak_var
; CHECK-LARGE: movk x0, #:abs_g2_nc:defined_weak_var
; CHECK-LARGE: movk x0, #:abs_g1_nc:defined_weak_var
; CHECK-LARGE: movk x0, #:abs_g0_nc:defined_weak_var
}