llvm-project/llvm/test/Transforms/SimplifyCFG/PhiNoEliminate.ll

28 lines
1.1 KiB
LLVM

; RUN: opt < %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S | \
; RUN: not grep select
;; The PHI node in this example should not be turned into a select, as we are
;; not able to ifcvt the entire block. As such, converting to a select just
;; introduces inefficiency without saving copies.
define i32 @bar(i1 %C) {
entry:
br i1 %C, label %then, label %endif
then: ; preds = %entry
%tmp.3 = call i32 @qux( ) ; <i32> [#uses=0]
br label %endif
endif: ; preds = %then, %entry
%R = phi i32 [ 123, %entry ], [ 12312, %then ] ; <i32> [#uses=1]
;; stuff to disable tail duplication
call i32 @qux( ) ; <i32>:0 [#uses=0]
call i32 @qux( ) ; <i32>:1 [#uses=0]
call i32 @qux( ) ; <i32>:2 [#uses=0]
call i32 @qux( ) ; <i32>:3 [#uses=0]
call i32 @qux( ) ; <i32>:4 [#uses=0]
call i32 @qux( ) ; <i32>:5 [#uses=0]
call i32 @qux( ) ; <i32>:6 [#uses=0]
ret i32 %R
}
declare i32 @qux()