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; RUN: opt < %s -phi-values -basic-aa -aa-eval -print-all-alias-modref-info -disable-output 2>&1 | FileCheck %s
; RUN: opt < %s -aa-pipeline=basic-aa -passes='require<phi-values>,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 i32* [ @X, %bb ], [ @Y, %bb1 ]
%tmp1 = load i32, i32* @Z, align 4
store i32 123, i32* %P, align 4
%tmp2 = load i32, i32* @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(i32* %jj7, i32* %j) {
entry:
%oa5 = alloca [100 x i32], align 16
br label %codeRepl
codeRepl:
%0 = phi i32* [ %arrayidx13, %for.body ], [ %j, %entry ]
%targetBlock = call i1 @cond(i32* %jj7)
br i1 %targetBlock, label %for.body, label %bye
for.body:
%1 = load i32, i32* %jj7, align 4
%idxprom4 = zext i32 %1 to i64
%arrayidx5 = getelementptr inbounds [100 x i32], [100 x i32]* %oa5, i64 0, i64 %idxprom4
%2 = load i32, i32* %arrayidx5, align 4
%sub6 = sub i32 %2, 6
store i32 %sub6, i32* %arrayidx5, align 4
; %0 and %arrayidx5 can alias! It is not safe to DSE the above store.
%3 = load i32, i32* %0, align 4
store i32 %3, i32* %arrayidx5, align 4
%sub11 = add i32 %1, -1
%idxprom12 = zext i32 %sub11 to i64
%arrayidx13 = getelementptr inbounds [100 x i32], [100 x i32]* %oa5, i64 0, i64 %idxprom12
call void @inc(i32* %jj7)
br label %codeRepl
bye:
%.reload = load i32, i32* %jj7, align 4
ret i32 %.reload
}
declare i1 @cond(i32*)
declare void @inc(i32*)
; When we have a chain of phis in nested loops we should recognise if there's
; actually only one underlying value.
; CHECK-LABEL: loop_phi_chain
; CHECK: NoAlias: i32* %val1, i32* @Y
; CHECK: NoAlias: i32* %val2, i32* @Y
; CHECK: NoAlias: 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 i32* [ @X, %entry ], [ %val2, %loop2 ]
%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 i32* [ %val1, %loop1 ], [ %val3, %loop3 ]
%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 i32* [ %val2, %loop2 ], [ %val3, %loop3 ]
store i32 0, i32* %val3, align 4
store i32 0, i32* @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, i32* %x, i32* %y) {
entry:
br i1 %c, label %true, label %false
true:
br label %exit
false:
br label %exit
exit:
%p = phi i32* [ %x, %true ], [ %y, %false ]
%s = select i1 %c2, i32* %p, i32* %p
store i32 0, i32* %p
store i32 0, i32* %s
ret void
}
; CHECK-LABEL: phi_and_phi_cycle
; CHECK: NoAlias: i32* %p1, i32* %p2
define void @phi_and_phi_cycle(i32* noalias %x, i32* noalias %y) {
entry:
br label %loop
loop:
%p1 = phi i32* [ %x, %entry ], [ %p1.next, %loop ]
%p2 = phi i32* [ %y, %entry ], [ %p2.next, %loop ]
%p1.next = getelementptr i32, i32* %p1, i64 1
%p2.next = getelementptr i32, i32* %p1, i64 2
store i32 0, i32* %p1
store i32 0, i32* %p2
br label %loop
}
; CHECK-LABEL: phi_and_gep_unknown_size
; CHECK: Just Mod: call void @llvm.memset.p0i8.i32(i8* %g, i8 0, i32 %size, i1 false) <-> call void @llvm.memset.p0i8.i32(i8* %z, i8 0, i32 %size, i1 false)
; TODO: This should be NoModRef.
define void @phi_and_gep_unknown_size(i1 %c, i8* %x, i8* %y, i8* noalias %z, i32 %size) {
entry:
br i1 %c, label %true, label %false
true:
br label %exit
false:
br label %exit
exit:
%p = phi i8* [ %x, %true ], [ %y, %false ]
%g = getelementptr inbounds i8, i8* %p, i64 1
call void @llvm.memset.p0i8.i32(i8* %g, i8 0, i32 %size, i1 false)
call void @llvm.memset.p0i8.i32(i8* %z, i8 0, i32 %size, i1 false)
ret void
}
declare void @llvm.memset.p0i8.i32(i8*, i8, i32, i1)
; CHECK-LABEL: unsound_inequality
; CHECK: MayAlias: i32* %arrayidx13, i32* %phi
; CHECK: MayAlias: i32* %arrayidx5, 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(i32* %jj7, i32* %j) {
entry:
%oa5 = alloca [100 x i32], align 16
br label %for.body
for.body: ; preds = %for.body, %entry
%phi = phi i32* [ %arrayidx13, %for.body ], [ %j, %entry ]
%idx = load i32, i32* %jj7, align 4
%arrayidx5 = getelementptr inbounds [100 x i32], [100 x i32]* %oa5, i64 0, i32 %idx
store i32 0, i32* %arrayidx5, align 4
store i32 0, i32* %phi, align 4
%notequal = add i32 %idx, 1
%arrayidx13 = getelementptr inbounds [100 x i32], [100 x i32]* %oa5, i64 0, i32 %notequal
store i32 0, i32* %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(i32* %ptr.base) {
entry:
br label %loop
loop:
%ptr = phi i32* [ %ptr.base, %entry ], [ %ptr.next, %split ]
%ptr.next = getelementptr inbounds i32, i32* %ptr, i64 1
br label %split
split:
%ptr.phi = phi i32* [ %ptr, %loop ]
%ptr.next.phi = phi i32* [ %ptr.next, %loop ]
br label %loop
}
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