llvm/test/CodeGen/AArch64/extern-weak.ll
Evandro Menezes f5697dce74 [AArch64] Generate literals by the little end
ARM seems to prefer that long literals be formed from their little end in
order to promote the fusion of the instrs pairs MOV/MOVK and MOVK/MOVK on
Cortex A57 and others (v.  "Cortex A57 Software Optimisation Guide", section
4.14).

Differential revision: https://reviews.llvm.org/D28697

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292422 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-18 18:57:08 +00:00

59 lines
1.9 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 %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]
; In the large model, the usual relocations are absolute and can
; materialise 0.
; CHECK-LARGE: movz x0, #:abs_g0_nc:var
; CHECK-LARGE: movk x0, #:abs_g1_nc:var
; CHECK-LARGE: movk x0, #:abs_g2_nc:var
; CHECK-LARGE: movk x0, #:abs_g3:var
}
@arr_var = extern_weak global [10 x i32]
define i32* @bar() {
%addr = getelementptr [10 x i32], [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
ret i32* %addr
; In the large model, the usual relocations are absolute and can
; materialise 0.
; CHECK-LARGE: movz [[ADDR:x[0-9]+]], #:abs_g0_nc:arr_var
; CHECK-LARGE: movk [[ADDR]], #:abs_g1_nc:arr_var
; CHECK-LARGE: movk [[ADDR]], #:abs_g2_nc:arr_var
; CHECK-LARGE: movk [[ADDR]], #:abs_g3: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-LARGE: movz x0, #:abs_g0_nc:defined_weak_var
; CHECK-LARGE: movk x0, #:abs_g1_nc:defined_weak_var
; CHECK-LARGE: movk x0, #:abs_g2_nc:defined_weak_var
; CHECK-LARGE: movk x0, #:abs_g3:defined_weak_var
}