llvm-mirror/test/CodeGen/AArch64/fold-global-offsets.ll
Peter Collingbourne b4b51eb3aa Reland r329956, "AArch64: Introduce a DAG combine for folding offsets into addresses.", with a fix for the bot failure.
This reland includes a check to prevent the DAG combiner from folding an
offset that is smaller than the existing one. This can cause oscillations
between two possible DAGs, which was the cause of the hang and later assertion
failure observed on the lnt-ctmark-aarch64-O3-flto bot.
http://green.lab.llvm.org/green/job/lnt-ctmark-aarch64-O3-flto/2024/

Original commit message:
> This is a code size win in code that takes offseted addresses
> frequently, such as C++ constructors that typically need to compute
> an offseted address of a vtable. This reduces the size of Chromium
> for Android's .text section by 108KB.

Differential Revision: https://reviews.llvm.org/D45199

llvm-svn: 330630
2018-04-23 19:09:34 +00:00

70 lines
2.0 KiB
LLVM

; RUN: llc < %s -mtriple=arm64-linux-gnu | FileCheck %s
@x1 = external hidden global [2 x i64]
@x2 = external hidden global [16777216 x i64]
@x3 = external hidden global { [9 x i8*], [8 x i8*] }
define i64 @f1() {
; CHECK: f1:
; CHECK: adrp x8, x1+16
; CHECK: ldr x0, [x8, :lo12:x1+16]
%l = load i64, i64* getelementptr ([2 x i64], [2 x i64]* @x1, i64 0, i64 2)
ret i64 %l
}
define i64 @f2() {
; CHECK: f2:
; CHECK: adrp x8, x1
; CHECK: add x8, x8, :lo12:x1
; CHECK: ldr x0, [x8, #24]
%l = load i64, i64* getelementptr ([2 x i64], [2 x i64]* @x1, i64 0, i64 3)
ret i64 %l
}
define i64 @f3() {
; CHECK: f3:
; CHECK: adrp x8, x1+1
; CHECK: add x8, x8, :lo12:x1+1
; CHECK: ldr x0, [x8]
%l = load i64, i64* bitcast (i8* getelementptr (i8, i8* bitcast ([2 x i64]* @x1 to i8*), i64 1) to i64*)
ret i64 %l
}
define [2 x i64] @f4() {
; CHECK: f4:
; CHECK: adrp x8, x2+8
; CHECK: add x8, x8, :lo12:x2+8
; CHECK: ldp x0, x1, [x8]
%l = load [2 x i64], [2 x i64]* bitcast (i8* getelementptr (i8, i8* bitcast ([16777216 x i64]* @x2 to i8*), i64 8) to [2 x i64]*)
ret [2 x i64] %l
}
define i64 @f5() {
; CHECK: f5:
; CHECK: adrp x8, x2+2097144
; CHECK: ldr x0, [x8, :lo12:x2+2097144]
; CHECK: ret
%l = load i64, i64* getelementptr ([16777216 x i64], [16777216 x i64]* @x2, i64 0, i64 262143)
ret i64 %l
}
define i64 @f6() {
; CHECK: f6:
; CHECK: adrp x8, x2
; CHECK: add x8, x8, :lo12:x2
; CHECK: orr w9, wzr, #0x200000
; CHECK: ldr x0, [x8, x9]
; CHECK: ret
%l = load i64, i64* getelementptr ([16777216 x i64], [16777216 x i64]* @x2, i64 0, i64 262144)
ret i64 %l
}
define i32 @f7() {
entry:
; CHECK: f7
; CHECK: adrp x8, x3+108
; CHECK: ldr w0, [x8, :lo12:x3+108]
%l = load i32, i32* getelementptr (i32, i32* inttoptr (i64 trunc (i128 lshr (i128 bitcast (<2 x i64> <i64 undef, i64 ptrtoint (i8** getelementptr inbounds ({ [9 x i8*], [8 x i8*] }, { [9 x i8*], [8 x i8*] }* @x3, i64 0, inrange i32 1, i64 2) to i64)> to i128), i128 64) to i64) to i32*), i64 5)
ret i32 %l
}