llvm-6502/test/Analysis/BasicAA/phi-and-select.ll
Dan Gohman 6665b0ea68 Teach BasicAA how to analyze Select instructions, and make it more
aggressive on PHI instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85158 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-26 21:55:43 +00:00

74 lines
1.8 KiB
LLVM

; RUN: opt < %s -aa-eval -print-all-alias-modref-info -disable-output \
; RUN: |& grep {NoAlias: double\\* \[%\]a, double\\* \[%\]b\$} | count 4
; BasicAA should detect NoAliases in PHIs and Selects.
; Two PHIs in the same block.
define void @foo(i1 %m, double* noalias %x, double* noalias %y) {
entry:
br i1 %m, label %true, label %false
true:
br label %exit
false:
br label %exit
exit:
%a = phi double* [ %x, %true ], [ %y, %false ]
%b = phi double* [ %x, %false ], [ %y, %true ]
volatile store double 0.0, double* %a
volatile store double 1.0, double* %b
ret void
}
; Two selects with the same condition.
define void @bar(i1 %m, double* noalias %x, double* noalias %y) {
entry:
%a = select i1 %m, double* %x, double* %y
%b = select i1 %m, double* %y, double* %x
volatile store double 0.000000e+00, double* %a
volatile store double 1.000000e+00, double* %b
ret void
}
; Two PHIs with disjoint sets of inputs.
define void @qux(i1 %m, double* noalias %x, double* noalias %y,
i1 %n, double* noalias %v, double* noalias %w) {
entry:
br i1 %m, label %true, label %false
true:
br label %exit
false:
br label %exit
exit:
%a = phi double* [ %x, %true ], [ %y, %false ]
br i1 %n, label %ntrue, label %nfalse
ntrue:
br label %nexit
nfalse:
br label %nexit
nexit:
%b = phi double* [ %v, %ntrue ], [ %w, %nfalse ]
volatile store double 0.0, double* %a
volatile store double 1.0, double* %b
ret void
}
; Two selects with disjoint sets of arms.
define void @fin(i1 %m, double* noalias %x, double* noalias %y,
i1 %n, double* noalias %v, double* noalias %w) {
entry:
%a = select i1 %m, double* %x, double* %y
%b = select i1 %n, double* %v, double* %w
volatile store double 0.000000e+00, double* %a
volatile store double 1.000000e+00, double* %b
ret void
}