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; RUN: opt < %s -aa-pipeline=basic-aa -passes=aa-eval -print-all-alias-modref-info -disable-output 2>&1 | FileCheck %s
; BasicAA should detect NoAliases in PHIs and Selects.
; Two PHIs in the same block.
; CHECK-LABEL: Function: foo
; CHECK: NoAlias: double* %a, double* %b
define void @foo(i1 %m, ptr noalias %x, ptr noalias %y) {
entry:
br i1 %m, label %true, label %false
true:
br label %exit
false:
br label %exit
exit:
%a = phi ptr [ %x, %true ], [ %y, %false ]
%b = phi ptr [ %x, %false ], [ %y, %true ]
store volatile double 0.0, ptr %a
store volatile double 1.0, ptr %b
ret void
}
; Two selects with the same condition.
; CHECK-LABEL: Function: bar
; CHECK: NoAlias: double* %a, double* %b
define void @bar(i1 %m, ptr noalias %x, ptr noalias %y) {
entry:
%a = select i1 %m, ptr %x, ptr %y
%b = select i1 %m, ptr %y, ptr %x
store volatile double 0.000000e+00, ptr %a
store volatile double 1.000000e+00, ptr %b
ret void
}
; Two PHIs with disjoint sets of inputs.
; CHECK-LABEL: Function: qux
; CHECK: NoAlias: double* %a, double* %b
define void @qux(i1 %m, ptr noalias %x, ptr noalias %y,
i1 %n, ptr noalias %v, ptr noalias %w) {
entry:
br i1 %m, label %true, label %false
true:
br label %exit
false:
br label %exit
exit:
%a = phi ptr [ %x, %true ], [ %y, %false ]
br i1 %n, label %ntrue, label %nfalse
ntrue:
br label %nexit
nfalse:
br label %nexit
nexit:
%b = phi ptr [ %v, %ntrue ], [ %w, %nfalse ]
store volatile double 0.0, ptr %a
store volatile double 1.0, ptr %b
ret void
}
; Two selects with disjoint sets of arms.
; CHECK-LABEL: Function: fin
; CHECK: NoAlias: double* %a, double* %b
define void @fin(i1 %m, ptr noalias %x, ptr noalias %y,
i1 %n, ptr noalias %v, ptr noalias %w) {
entry:
%a = select i1 %m, ptr %x, ptr %y
%b = select i1 %n, ptr %v, ptr %w
store volatile double 0.000000e+00, ptr %a
store volatile double 1.000000e+00, ptr %b
ret void
}
; On the first iteration, sel1 = a1, sel2 = a2, phi = a3
; On the second iteration, sel1 = a2, sel1 = a1, phi = a2
; As such, sel1 and phi may alias.
; CHECK-LABEL: Function: select_backedge
; CHECK: NoAlias: i32* %sel1, i32* %sel2
; CHECK: MayAlias: i32* %phi, i32* %sel1
; CHECK: MayAlias: i32* %phi, i32* %sel2
define void @select_backedge() {
entry:
%a1 = alloca i32
%a2 = alloca i32
%a3 = alloca i32
br label %loop
loop:
%phi = phi ptr [ %a3, %entry ], [ %sel2, %loop ]
%c = phi i1 [ true, %entry ], [ false, %loop ]
%sel1 = select i1 %c, ptr %a1, ptr %a2
%sel2 = select i1 %c, ptr %a2, ptr %a1
load i32, ptr %sel1
load i32, ptr %sel2
load i32, ptr %phi
br label %loop
}
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