; RUN: opt < %s -aa-pipeline=basic-aa -passes=aa-eval -print-all-alias-modref-info -disable-output 2>&1 | FileCheck %s ;; Simple case: a zext nneg can be replaced with a sext. Make sure BasicAA ;; understands that. define void @t1(i32 %a, i32 %b) { ; CHECK-LABEL: Function: t1 ; CHECK: NoAlias: float* %gep1, float* %gep2 %1 = alloca [8 x float], align 4 %or1 = or i32 %a, 1 %2 = sext i32 %or1 to i64 %gep1 = getelementptr inbounds float, ptr %1, i64 %2 %shl1 = shl i32 %b, 1 %3 = zext nneg i32 %shl1 to i64 %gep2 = getelementptr inbounds float, ptr %1, i64 %3 load float, ptr %gep1 load float, ptr %gep2 ret void } ;; A (zext nneg (sext V)) is equivalent to a (zext (sext V)) as long as the ;; total number of zext+sext bits is the same for both. define void @t2(i8 %a, i8 %b) { ; CHECK-LABEL: Function: t2 ; CHECK: NoAlias: float* %gep1, float* %gep2 %1 = alloca [8 x float], align 4 %or1 = or i8 %a, 1 %2 = sext i8 %or1 to i32 %3 = zext i32 %2 to i64 %gep1 = getelementptr inbounds float, ptr %1, i64 %3 %shl1 = shl i8 %b, 1 %4 = sext i8 %shl1 to i16 %5 = zext nneg i16 %4 to i64 %gep2 = getelementptr inbounds float, ptr %1, i64 %5 load float, ptr %gep1 load float, ptr %gep2 ret void } ;; Here the %a and %b are knowably non-equal. In this cases we can distribute ;; the zext, preserving the nneg flag, through the shl because it has a nsw flag define void @t3(i8 %v) { ; CHECK-LABEL: Function: t3 ; CHECK: NoAlias: <2 x float>* %gep1, <2 x float>* %gep2 %a = or i8 %v, 1 %b = and i8 %v, 2 %1 = alloca [8 x float], align 4 %or1 = shl nuw nsw i8 %a, 1 %2 = zext nneg i8 %or1 to i64 %gep1 = getelementptr inbounds float, ptr %1, i64 %2 %m = mul nsw nuw i8 %b, 2 %3 = sext i8 %m to i16 %4 = zext i16 %3 to i64 %gep2 = getelementptr inbounds float, ptr %1, i64 %4 load <2 x float>, ptr %gep1 load <2 x float>, ptr %gep2 ret void } ;; This is the same as above, but this time the shl does not have the nsw flag. ;; the nneg cannot be kept on the zext. define void @t4(i8 %v) { ; CHECK-LABEL: Function: t4 ; CHECK: MayAlias: <2 x float>* %gep1, <2 x float>* %gep2 %a = or i8 %v, 1 %b = and i8 %v, 2 %1 = alloca [8 x float], align 4 %or1 = shl nuw i8 %a, 1 %2 = zext nneg i8 %or1 to i64 %gep1 = getelementptr inbounds float, ptr %1, i64 %2 %m = mul nsw nuw i8 %b, 2 %3 = sext i8 %m to i16 %4 = zext i16 %3 to i64 %gep2 = getelementptr inbounds float, ptr %1, i64 %4 load <2 x float>, ptr %gep1 load <2 x float>, ptr %gep2 ret void } ;; Verify a zext nneg and a zext are understood as the same define void @t5(ptr %p, i16 %i) { ; CHECK-LABEL: Function: t5 ; CHECK: NoAlias: i32* %pi, i32* %pi.next %i1 = zext nneg i16 %i to i32 %pi = getelementptr i32, ptr %p, i32 %i1 %i.next = add i16 %i, 1 %i.next2 = zext i16 %i.next to i32 %pi.next = getelementptr i32, ptr %p, i32 %i.next2 load i32, ptr %pi load i32, ptr %pi.next ret void } ;; This is not very idiomatic, but still possible, verify the nneg is propagated ;; outward. and that no alias is correctly identified. define void @t6(i8 %a) { ; CHECK-LABEL: Function: t6 ; CHECK: NoAlias: float* %gep1, float* %gep2 %1 = alloca [8 x float], align 4 %a.add = add i8 %a, 1 %2 = zext nneg i8 %a.add to i16 %3 = sext i16 %2 to i32 %4 = zext i32 %3 to i64 %gep1 = getelementptr inbounds float, ptr %1, i64 %4 %5 = sext i8 %a to i64 %gep2 = getelementptr inbounds float, ptr %1, i64 %5 load float, ptr %gep1 load float, ptr %gep2 ret void } ;; This is even less idiomatic, but still possible, verify the nneg is not ;; propagated inward. and that may alias is correctly identified. define void @t7(i8 %a) { ; CHECK-LABEL: Function: t7 ; CHECK: MayAlias: float* %gep1, float* %gep2 %1 = alloca [8 x float], align 4 %a.add = add i8 %a, 1 %2 = zext i8 %a.add to i16 %3 = sext i16 %2 to i32 %4 = zext nneg i32 %3 to i64 %gep1 = getelementptr inbounds float, ptr %1, i64 %4 %5 = sext i8 %a to i64 %gep2 = getelementptr inbounds float, ptr %1, i64 %5 load float, ptr %gep1 load float, ptr %gep2 ret void } ;; Verify the nneg survives an implicit trunc of fewer bits then the zext. define void @t8(i8 %a) { ; CHECK-LABEL: Function: t8 ; CHECK: NoAlias: float* %gep1, float* %gep2 %1 = alloca [8 x float], align 4 %a.add = add i8 %a, 1 %2 = zext nneg i8 %a.add to i128 %gep1 = getelementptr inbounds float, ptr %1, i128 %2 %3 = sext i8 %a to i64 %gep2 = getelementptr inbounds float, ptr %1, i64 %3 load float, ptr %gep1 load float, ptr %gep2 ret void } ;; Ensure that the nneg is never propagated past this trunc and that these ;; casted values are understood as non-equal. define void @t9(i8 %a) { ; CHECK-LABEL: Function: t9 ; CHECK: MayAlias: float* %gep1, float* %gep2 %1 = alloca [8 x float], align 4 %a.add = add i8 %a, 1 %2 = zext i8 %a.add to i16 %3 = trunc i16 %2 to i1 %4 = zext nneg i1 %3 to i64 %gep1 = getelementptr inbounds float, ptr %1, i64 %4 %5 = sext i8 %a to i64 %gep2 = getelementptr inbounds float, ptr %1, i64 %5 load float, ptr %gep1 load float, ptr %gep2 ret void }