; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=arm64-eabi | FileCheck %s
; Optimize expanded SRL/SHL used as an input of
; SETCC comparing it with zero by removing rotation.
;
; See https://bugs.llvm.org/show_bug.cgi?id=50197
define i128 @opt_setcc_lt_power_of_2(i128 %a) nounwind {
; CHECK-LABEL: opt_setcc_lt_power_of_2:
; CHECK: // %bb.0:
; CHECK-NEXT: .LBB0_1: // %loop
; CHECK-NEXT: // =>This Inner Loop Header: Depth=1
; CHECK-NEXT: adds x0, x0, #1
; CHECK-NEXT: cinc x1, x1, hs
; CHECK-NEXT: orr x8, x1, x0, lsr #60
; CHECK-NEXT: cbnz x8, .LBB0_1
; CHECK-NEXT: // %bb.2: // %exit
; CHECK-NEXT: ret
br label %loop
loop:
%phi.a = phi i128 [ %a, %0 ], [ %inc, %loop ]
%inc = add i128 %phi.a, 1
%cmp = icmp ult i128 %inc, 1152921504606846976
br i1 %cmp, label %exit, label %loop
exit:
ret i128 %inc
}
define i1 @opt_setcc_srl_eq_zero(i128 %a) nounwind {
; CHECK-LABEL: opt_setcc_srl_eq_zero:
; CHECK: // %bb.0:
; CHECK-NEXT: orr x8, x1, x0, lsr #17
; CHECK-NEXT: cmp x8, #0
; CHECK-NEXT: cset w0, eq
; CHECK-NEXT: ret
%srl = lshr i128 %a, 17
%cmp = icmp eq i128 %srl, 0
ret i1 %cmp
}
define i1 @opt_setcc_srl_ne_zero(i128 %a) nounwind {
; CHECK-LABEL: opt_setcc_srl_ne_zero:
; CHECK: // %bb.0:
; CHECK-NEXT: orr x8, x1, x0, lsr #17
; CHECK-NEXT: cmp x8, #0
; CHECK-NEXT: cset w0, ne
; CHECK-NEXT: ret
%srl = lshr i128 %a, 17
%cmp = icmp ne i128 %srl, 0
ret i1 %cmp
}
define i1 @opt_setcc_shl_eq_zero(i128 %a) nounwind {
; CHECK-LABEL: opt_setcc_shl_eq_zero:
; CHECK: // %bb.0:
; CHECK-NEXT: orr x8, x0, x1, lsl #17
; CHECK-NEXT: cmp x8, #0
; CHECK-NEXT: cset w0, eq
; CHECK-NEXT: ret
%shl = shl i128 %a, 17
%cmp = icmp eq i128 %shl, 0
ret i1 %cmp
}
define i1 @opt_setcc_shl_ne_zero(i128 %a) nounwind {
; CHECK-LABEL: opt_setcc_shl_ne_zero:
; CHECK: // %bb.0:
; CHECK-NEXT: orr x8, x0, x1, lsl #17
; CHECK-NEXT: cmp x8, #0
; CHECK-NEXT: cset w0, ne
; CHECK-NEXT: ret
%shl = shl i128 %a, 17
%cmp = icmp ne i128 %shl, 0
ret i1 %cmp
}
; Negative test: optimization should not be applied if shift has multiple users.
define i1 @opt_setcc_shl_eq_zero_multiple_shl_users(i128 %a) nounwind {
; CHECK-LABEL: opt_setcc_shl_eq_zero_multiple_shl_users:
; CHECK: // %bb.0:
; CHECK-NEXT: stp x30, x19, [sp, #-16]! // 16-byte Folded Spill
; CHECK-NEXT: extr x1, x1, x0, #47
; CHECK-NEXT: lsl x0, x0, #17
; CHECK-NEXT: orr x8, x0, x1
; CHECK-NEXT: cmp x8, #0
; CHECK-NEXT: cset w19, eq
; CHECK-NEXT: bl use
; CHECK-NEXT: mov w0, w19
; CHECK-NEXT: ldp x30, x19, [sp], #16 // 16-byte Folded Reload
; CHECK-NEXT: ret
%shl = shl i128 %a, 17
%cmp = icmp eq i128 %shl, 0
call void @use(i128 %shl)
ret i1 %cmp
}
; Check that optimization is applied to DAG having appropriate shape
; even if there were no actual shift's expansion.
define i1 @opt_setcc_expanded_shl_correct_shifts(i64 %a, i64 %b) nounwind {
; CHECK-LABEL: opt_setcc_expanded_shl_correct_shifts:
; CHECK: // %bb.0:
; CHECK-NEXT: orr x8, x1, x0, lsl #17
; CHECK-NEXT: cmp x8, #0
; CHECK-NEXT: cset w0, eq
; CHECK-NEXT: ret
%shl.a = shl i64 %a, 17
%srl.b = lshr i64 %b, 47
%or.0 = or i64 %shl.a, %srl.b
%shl.b = shl i64 %b, 17
%or.1 = or i64 %or.0, %shl.b
%cmp = icmp eq i64 %or.1, 0
ret i1 %cmp
}
; Negative test: optimization should not be applied as
; constants used in shifts do not match.
define i1 @opt_setcc_expanded_shl_wrong_shifts(i64 %a, i64 %b) nounwind {
; CHECK-LABEL: opt_setcc_expanded_shl_wrong_shifts:
; CHECK: // %bb.0:
; CHECK-NEXT: extr x8, x0, x1, #47
; CHECK-NEXT: orr x8, x8, x1, lsl #18
; CHECK-NEXT: cmp x8, #0
; CHECK-NEXT: cset w0, eq
; CHECK-NEXT: ret
%shl.a = shl i64 %a, 17
%srl.b = lshr i64 %b, 47
%or.0 = or i64 %shl.a, %srl.b
%shl.b = shl i64 %b, 18
%or.1 = or i64 %or.0, %shl.b
%cmp = icmp eq i64 %or.1, 0
ret i1 %cmp
}
define i1 @opt_setcc_shl_ne_zero_i256(i256 %a) nounwind {
; CHECK-LABEL: opt_setcc_shl_ne_zero_i256:
; CHECK: // %bb.0:
; CHECK-NEXT: orr x8, x2, x0
; CHECK-NEXT: orr x8, x1, x8
; CHECK-NEXT: orr x8, x8, x3, lsl #17
; CHECK-NEXT: cmp x8, #0
; CHECK-NEXT: cset w0, ne
; CHECK-NEXT: ret
%shl = shl i256 %a, 17
%cmp = icmp ne i256 %shl, 0
ret i1 %cmp
}
declare void @use(i128 %a)
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