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|
# RUN: llc -run-pass=prologepilog -reverse-csr-restore-seq -o - -mtriple=aarch64-- %s | FileCheck %s --check-prefixes=CHECK,BEFORELDSTOPT
# RUN: llc -start-before=prologepilog -stop-after=aarch64-ldst-opt -reverse-csr-restore-seq -o - -mtriple=aarch64-- %s | FileCheck %s --check-prefixes=CHECK,AFTERLDSTOPT
#
--- |
define void @foo() nounwind { entry: unreachable }
define void @bar() nounwind { entry: unreachable }
...
---
name: foo
# CHECK-LABEL: name: foo
tracksRegLiveness: true
body: |
bb.0:
$x19 = IMPLICIT_DEF
$x20 = IMPLICIT_DEF
$x21 = IMPLICIT_DEF
$x22 = IMPLICIT_DEF
$x23 = IMPLICIT_DEF
$x24 = IMPLICIT_DEF
$x25 = IMPLICIT_DEF
$x26 = IMPLICIT_DEF
; The local stack size is 0, so the last ldp in the sequence will also
; restore the stack.
; CHECK: $x24, $x23 = frame-destroy LDPXi $sp, 2
; CHECK-NEXT: $x22, $x21 = frame-destroy LDPXi $sp, 4
; CHECK-NEXT: $x20, $x19 = frame-destroy LDPXi $sp, 6
; Before running the load-store optimizer, we emit a ldp and an add.
; BEFORELDSTOPT-NEXT: $x26, $x25 = frame-destroy LDPXi $sp, 0
; BEFORELDSTOPT-NEXT: $sp = frame-destroy ADDXri $sp, 64, 0
; We want to make sure that after running the load-store optimizer, the ldp
; and the add get merged into a post-index ldp.
; AFTERLDSTOPT-NEXT: early-clobber $sp, $x26, $x25 = frame-destroy LDPXpost $sp, 8
RET_ReallyLR
...
---
name: bar
# CHECK-LABEL: name: bar
tracksRegLiveness: true
stack:
- { id : 0, size: 8, alignment: 4,
stack-id: 0, callee-saved-register: '', callee-saved-restored: true,
local-offset: -4, di-variable: '', di-expression: '', di-location: '' }
body: |
bb.0:
$x19 = IMPLICIT_DEF
$x20 = IMPLICIT_DEF
$x21 = IMPLICIT_DEF
$x22 = IMPLICIT_DEF
$x23 = IMPLICIT_DEF
$x24 = IMPLICIT_DEF
$x25 = IMPLICIT_DEF
$x26 = IMPLICIT_DEF
; The local stack size is not 0, and we can combine the CSR stack size with
; the local stack size. This results in rewriting the offsets for all the
; save/restores and forbids us to merge the stack adjustment and the last pop.
; In this case, there is no point of moving the first CSR pair at the end.
; CHECK: $x26, $x25 = frame-destroy LDPXi $sp, 2
; CHECK-NEXT: $x24, $x23 = frame-destroy LDPXi $sp, 4
; CHECK-NEXT: $x22, $x21 = frame-destroy LDPXi $sp, 6
; CHECK-NEXT: $x20, $x19 = frame-destroy LDPXi $sp, 8
; CHECK-NEXT: $sp = frame-destroy ADDXri $sp, 80, 0
RET_ReallyLR
...
|
