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; RUN: llvm-upgrade < %s | llvm-as | opt -simplifycfg | llvm-dis | \
; RUN: not grep {call void %DEAD}
; Test that we can thread a simple known condition through switch statements.
declare void %foo1()
declare void %foo2()
declare void %DEAD()
void %test1(uint %V) {
switch uint %V, label %A [
uint 4, label %T
uint 17, label %Done
uint 1234, label %A
]
T: ;; V == 4 if we get here.
call void %foo1()
;; This switch is always statically determined.
switch uint %V, label %A2 [
uint 4, label %B
uint 17, label %C
uint 42, label %C
]
A2:
call void %DEAD()
call void %DEAD()
%cond2 = seteq uint %V, 4 ;; always false
br bool %cond2, label %Done, label %C
A:
call void %foo1()
%cond = setne uint %V, 4 ;; always true
br bool %cond, label %Done, label %C
Done:
ret void
B:
call void %foo2()
%cond3 = seteq uint %V, 4 ;; always true
br bool %cond3, label %Done, label %C
C:
call void %DEAD()
ret void
}
void %test2(uint %V) {
switch uint %V, label %A [
uint 4, label %T
uint 17, label %D
uint 1234, label %E
]
A: ;; V != 4, 17, 1234 here.
call void %foo1()
;; This switch is always statically determined.
switch uint %V, label %E [
uint 4, label %C
uint 17, label %C
uint 42, label %D
]
C:
call void %DEAD() ;; unreacahble.
ret void
T:
call void %foo1()
call void %foo1()
ret void
D:
call void %foo1()
ret void
E:
ret void
}
|
