; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py ; RUN: llc -mtriple=aarch64-unknown-linux-gnu < %s | FileCheck %s ; Fold ; ptr - (ptr & (alignment-1)) ; To ; ptr & (0 - alignment) ; ; This needs to be a backend-level fold because only by now pointers ; are just registers; in middle-end IR this can only be done via @llvm.ptrmask() ; intrinsic which is not sufficiently widely-spread yet. ; ; https://bugs.llvm.org/show_bug.cgi?id=44448 ; The basic positive tests define i32 @t0_32(i32 %ptr, i32 %alignment) nounwind { ; CHECK-LABEL: t0_32: ; CHECK: // %bb.0: ; CHECK-NEXT: neg w8, w1 ; CHECK-NEXT: and w0, w0, w8 ; CHECK-NEXT: ret %mask = add i32 %alignment, -1 %bias = and i32 %ptr, %mask %r = sub i32 %ptr, %bias ret i32 %r } define i64 @t1_64(i64 %ptr, i64 %alignment) nounwind { ; CHECK-LABEL: t1_64: ; CHECK: // %bb.0: ; CHECK-NEXT: neg x8, x1 ; CHECK-NEXT: and x0, x0, x8 ; CHECK-NEXT: ret %mask = add i64 %alignment, -1 %bias = and i64 %ptr, %mask %r = sub i64 %ptr, %bias ret i64 %r } define i32 @t2_commutative(i32 %ptr, i32 %alignment) nounwind { ; CHECK-LABEL: t2_commutative: ; CHECK: // %bb.0: ; CHECK-NEXT: neg w8, w1 ; CHECK-NEXT: and w0, w0, w8 ; CHECK-NEXT: ret %mask = add i32 %alignment, -1 %bias = and i32 %mask, %ptr ; swapped %r = sub i32 %ptr, %bias ret i32 %r } ; Extra use tests define i32 @t3_extrause0(i32 %ptr, i32 %alignment, i32* %mask_storage) nounwind { ; CHECK-LABEL: t3_extrause0: ; CHECK: // %bb.0: ; CHECK-NEXT: neg w8, w1 ; CHECK-NEXT: and w0, w0, w8 ; CHECK-NEXT: sub w8, w1, #1 ; CHECK-NEXT: str w8, [x2] ; CHECK-NEXT: ret %mask = add i32 %alignment, -1 store i32 %mask, i32* %mask_storage %bias = and i32 %ptr, %mask %r = sub i32 %ptr, %bias ret i32 %r } define i32 @n4_extrause1(i32 %ptr, i32 %alignment, i32* %bias_storage) nounwind { ; CHECK-LABEL: n4_extrause1: ; CHECK: // %bb.0: ; CHECK-NEXT: sub w8, w1, #1 ; CHECK-NEXT: and w8, w0, w8 ; CHECK-NEXT: sub w0, w0, w8 ; CHECK-NEXT: str w8, [x2] ; CHECK-NEXT: ret %mask = add i32 %alignment, -1 %bias = and i32 %ptr, %mask ; has extra uses, can't fold store i32 %bias, i32* %bias_storage %r = sub i32 %ptr, %bias ret i32 %r } define i32 @n5_extrause2(i32 %ptr, i32 %alignment, i32* %mask_storage, i32* %bias_storage) nounwind { ; CHECK-LABEL: n5_extrause2: ; CHECK: // %bb.0: ; CHECK-NEXT: sub w8, w1, #1 ; CHECK-NEXT: and w9, w0, w8 ; CHECK-NEXT: sub w0, w0, w9 ; CHECK-NEXT: str w8, [x2] ; CHECK-NEXT: str w9, [x3] ; CHECK-NEXT: ret %mask = add i32 %alignment, -1 store i32 %mask, i32* %mask_storage %bias = and i32 %ptr, %mask ; has extra uses, can't fold store i32 %bias, i32* %bias_storage %r = sub i32 %ptr, %bias ret i32 %r } ; Negative tests define i32 @n6_different_ptrs(i32 %ptr0, i32 %ptr1, i32 %alignment) nounwind { ; CHECK-LABEL: n6_different_ptrs: ; CHECK: // %bb.0: ; CHECK-NEXT: sub w8, w2, #1 ; CHECK-NEXT: and w8, w1, w8 ; CHECK-NEXT: sub w0, w0, w8 ; CHECK-NEXT: ret %mask = add i32 %alignment, -1 %bias = and i32 %ptr1, %mask ; not %ptr0 %r = sub i32 %ptr0, %bias ; not %ptr1 ret i32 %r } define i32 @n7_different_ptrs_commutative(i32 %ptr0, i32 %ptr1, i32 %alignment) nounwind { ; CHECK-LABEL: n7_different_ptrs_commutative: ; CHECK: // %bb.0: ; CHECK-NEXT: sub w8, w2, #1 ; CHECK-NEXT: and w8, w8, w1 ; CHECK-NEXT: sub w0, w0, w8 ; CHECK-NEXT: ret %mask = add i32 %alignment, -1 %bias = and i32 %mask, %ptr1 ; swapped, not %ptr0 %r = sub i32 %ptr0, %bias ; not %ptr1 ret i32 %r } define i32 @n8_not_lowbit_mask(i32 %ptr, i32 %alignment) nounwind { ; CHECK-LABEL: n8_not_lowbit_mask: ; CHECK: // %bb.0: ; CHECK-NEXT: add w8, w1, #1 ; CHECK-NEXT: bic w0, w0, w8 ; CHECK-NEXT: ret %mask = add i32 %alignment, 1 ; not -1 %bias = and i32 %ptr, %mask %r = sub i32 %ptr, %bias ret i32 %r } define i32 @n9_sub_is_not_commutative(i32 %ptr, i32 %alignment) nounwind { ; CHECK-LABEL: n9_sub_is_not_commutative: ; CHECK: // %bb.0: ; CHECK-NEXT: sub w8, w1, #1 ; CHECK-NEXT: and w8, w0, w8 ; CHECK-NEXT: sub w0, w8, w0 ; CHECK-NEXT: ret %mask = add i32 %alignment, -1 %bias = and i32 %ptr, %mask %r = sub i32 %bias, %ptr ; wrong order ret i32 %r }