; RUN: opt < %s -aa-pipeline=basic-aa -passes=aa-eval -print-all-alias-modref-info -disable-output 2>&1 | FileCheck %s target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" ; rdar://7282591 @X = common global i32 0 @Y = common global i32 0 @Z = common global i32 0 ; CHECK-LABEL: foo ; CHECK: NoAlias: i32* %P, i32* @Z define void @foo(i32 %cond) nounwind { entry: %"alloca point" = bitcast i32 0 to i32 %tmp = icmp ne i32 %cond, 0 br i1 %tmp, label %bb, label %bb1 bb: br label %bb2 bb1: br label %bb2 bb2: %P = phi ptr [ @X, %bb ], [ @Y, %bb1 ] %tmp1 = load i32, ptr @Z, align 4 store i32 123, ptr %P, align 4 %tmp2 = load i32, ptr @Z, align 4 br label %return return: ret void } ; Pointers can vary in between iterations of loops. ; PR18068 ; CHECK-LABEL: pr18068 ; CHECK: MayAlias: i32* %0, i32* %arrayidx5 ; CHECK: NoAlias: i32* %arrayidx13, i32* %arrayidx5 define i32 @pr18068(ptr %jj7, ptr %j) { entry: %oa5 = alloca [100 x i32], align 16 br label %codeRepl codeRepl: %0 = phi ptr [ %arrayidx13, %for.body ], [ %j, %entry ] %targetBlock = call i1 @cond(ptr %jj7) br i1 %targetBlock, label %for.body, label %bye for.body: %1 = load i32, ptr %jj7, align 4 %idxprom4 = zext i32 %1 to i64 %arrayidx5 = getelementptr inbounds [100 x i32], ptr %oa5, i64 0, i64 %idxprom4 %2 = load i32, ptr %arrayidx5, align 4 %sub6 = sub i32 %2, 6 store i32 %sub6, ptr %arrayidx5, align 4 ; %0 and %arrayidx5 can alias! It is not safe to DSE the above store. %3 = load i32, ptr %0, align 4 store i32 %3, ptr %arrayidx5, align 4 %sub11 = add i32 %1, -1 %idxprom12 = zext i32 %sub11 to i64 %arrayidx13 = getelementptr inbounds [100 x i32], ptr %oa5, i64 0, i64 %idxprom12 load i32, ptr %arrayidx13 call void @inc(ptr %jj7) br label %codeRepl bye: %.reload = load i32, ptr %jj7, align 4 ret i32 %.reload } declare i1 @cond(ptr) declare void @inc(ptr) ; When we have a chain of phis in nested loops we should recognise if there's ; actually only one underlying value. ; FIXME: All of these could be NoAlias. ; CHECK-LABEL: loop_phi_chain ; CHECK: MayAlias: i32* %val1, i32* @Y ; CHECK: MayAlias: i32* %val2, i32* @Y ; CHECK: MayAlias: i32* %val3, i32* @Y define void @loop_phi_chain(i32 %a, i32 %b, i32 %c) { entry: br label %loop1 loop1: %n1 = phi i32 [ 0, %entry ], [ %add1, %loop2 ] %val1 = phi ptr [ @X, %entry ], [ %val2, %loop2 ] load i32, ptr %val1 %add1 = add i32 %n1, 1 %cmp1 = icmp ne i32 %n1, 32 br i1 %cmp1, label %loop2, label %end loop2: %n2 = phi i32 [ 0, %loop1 ], [ %add2, %loop3 ] %val2 = phi ptr [ %val1, %loop1 ], [ %val3, %loop3 ] load i32, ptr %val2 %add2 = add i32 %n2, 1 %cmp2 = icmp ne i32 %n2, 32 br i1 %cmp2, label %loop3, label %loop1 loop3: %n3 = phi i32 [ 0, %loop2 ], [ %add3, %loop3 ] %val3 = phi ptr [ %val2, %loop2 ], [ %val3, %loop3 ] store i32 0, ptr %val3, align 4 store i32 0, ptr @Y, align 4 %add3 = add i32 %n3, 1 %cmp3 = icmp ne i32 %n3, 32 br i1 %cmp3, label %loop3, label %loop2 end: ret void } ; CHECK-LABEL: phi_and_select ; CHECK: MustAlias: i32* %p, i32* %s define void @phi_and_select(i1 %c, i1 %c2, ptr %x, ptr %y) { entry: br i1 %c, label %true, label %false true: br label %exit false: br label %exit exit: %p = phi ptr [ %x, %true ], [ %y, %false ] %s = select i1 %c2, ptr %p, ptr %p store i32 0, ptr %p store i32 0, ptr %s ret void } ; CHECK-LABEL: phi_and_phi_cycle ; CHECK: NoAlias: i32* %p1, i32* %p2 define void @phi_and_phi_cycle(ptr noalias %x, ptr noalias %y) { entry: br label %loop loop: %p1 = phi ptr [ %x, %entry ], [ %p1.next, %loop ] %p2 = phi ptr [ %y, %entry ], [ %p2.next, %loop ] %p1.next = getelementptr i32, ptr %p1, i64 1 %p2.next = getelementptr i32, ptr %p1, i64 2 store i32 0, ptr %p1 store i32 0, ptr %p2 br label %loop } ; CHECK-LABEL: phi_and_gep_unknown_size ; CHECK: Just Mod: call void @llvm.memset.p0.i32(ptr %g, i8 0, i32 %size, i1 false) <-> call void @llvm.memset.p0.i32(ptr %z, i8 0, i32 %size, i1 false) ; TODO: This should be NoModRef. define void @phi_and_gep_unknown_size(i1 %c, ptr %x, ptr %y, ptr noalias %z, i32 %size) { entry: br i1 %c, label %true, label %false true: br label %exit false: br label %exit exit: %p = phi ptr [ %x, %true ], [ %y, %false ] %g = getelementptr inbounds i8, ptr %p, i64 1 call void @llvm.memset.p0.i32(ptr %g, i8 0, i32 %size, i1 false) call void @llvm.memset.p0.i32(ptr %z, i8 0, i32 %size, i1 false) ret void } declare void @llvm.memset.p0.i32(ptr, i8, i32, i1) ; CHECK-LABEL: unsound_inequality ; CHECK: MayAlias: i32* %arrayidx5, i32* %phi ; CHECK: MayAlias: i32* %arrayidx13, i32* %phi ; CHECK: NoAlias: i32* %arrayidx13, i32* %arrayidx5 ; When recursively reasoning about phis, we can't use predicates between ; two values as we might be comparing the two from different iterations. define i32 @unsound_inequality(ptr %jj7, ptr %j) { entry: %oa5 = alloca [100 x i32], align 16 br label %for.body for.body: ; preds = %for.body, %entry %phi = phi ptr [ %arrayidx13, %for.body ], [ %j, %entry ] load i32, ptr %phi %idx = load i32, ptr %jj7, align 4 %arrayidx5 = getelementptr inbounds [100 x i32], ptr %oa5, i64 0, i32 %idx store i32 0, ptr %arrayidx5, align 4 store i32 0, ptr %phi, align 4 %notequal = add i32 %idx, 1 %arrayidx13 = getelementptr inbounds [100 x i32], ptr %oa5, i64 0, i32 %notequal store i32 0, ptr %arrayidx13, align 4 br label %for.body } ; CHECK-LABEL: single_arg_phi ; CHECK: NoAlias: i32* %ptr, i32* %ptr.next ; CHECK: MustAlias: i32* %ptr, i32* %ptr.phi ; CHECK: MustAlias: i32* %ptr.next, i32* %ptr.next.phi define void @single_arg_phi(ptr %ptr.base) { entry: br label %loop loop: %ptr = phi ptr [ %ptr.base, %entry ], [ %ptr.next, %split ] %ptr.next = getelementptr inbounds i32, ptr %ptr, i64 1 load i32, ptr %ptr load i32, ptr %ptr.next br label %split split: %ptr.phi = phi ptr [ %ptr, %loop ] %ptr.next.phi = phi ptr [ %ptr.next, %loop ] load i32, ptr %ptr.phi load i32, ptr %ptr.next.phi br label %loop } ; CHECK-LABEL: phi_of_geps_based_on_alloca ; CHECK: NoAlias: i32* %gep3, i32* %phi define void @phi_of_geps_based_on_alloca(i1 %c) { %a = alloca [3 x i32] br i1 %c, label %if, label %else if: %gep1 = getelementptr i32, ptr %a, i64 1 br label %join else: %gep2 = getelementptr i32, ptr %a, i64 2 br label %join join: %phi = phi ptr [ %gep1, %if ], [ %gep2, %else ] %gep3 = getelementptr i32, ptr %a, i64 3 load i32, ptr %phi load i32, ptr %gep3 ret void } ; Don't crash with an unreachable predecessor. ; CHECK-LABEL: pr59360 ; CHECK: MayAlias: i32* %loaded.ptr, i32* %phi define void @pr59360() { entry: br label %outer loopexit: ; No predecessors! br label %outer outer: ; preds = %loopexit, %entry %phi = phi ptr [ %loaded.ptr, %loopexit ], [ null, %entry ] store i32 0, ptr %phi, align 4 %loaded.ptr = load ptr, ptr null, align 8 %0 = load i32, ptr %loaded.ptr, align 4 ret void }