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; RUN: opt < %s -passes=tailcallelim -verify-dom-info -S | FileCheck %s
; PR7328
; PR7506
define i32 @test1_constants(i32 %x) {
entry:
%cond = icmp ugt i32 %x, 0 ; <i1> [#uses=1]
br i1 %cond, label %return, label %body
body: ; preds = %entry
%y = add i32 %x, 1 ; <i32> [#uses=1]
%recurse = call i32 @test1_constants(i32 %y) ; <i32> [#uses=0]
ret i32 0
return: ; preds = %entry
ret i32 1
}
; CHECK-LABEL: define i32 @test1_constants(
; CHECK: tailrecurse:
; CHECK: %ret.tr = phi i32 [ poison, %entry ], [ %current.ret.tr, %body ]
; CHECK: %ret.known.tr = phi i1 [ false, %entry ], [ true, %body ]
; CHECK: body:
; CHECK-NOT: %recurse
; CHECK: %current.ret.tr = select i1 %ret.known.tr, i32 %ret.tr, i32 0
; CHECK-NOT: ret
; CHECK: return:
; CHECK: %current.ret.tr1 = select i1 %ret.known.tr, i32 %ret.tr, i32 1
; CHECK: ret i32 %current.ret.tr1
define i32 @test2_non_constants(i32 %x) {
entry:
%cond = icmp ugt i32 %x, 0
br i1 %cond, label %return, label %body
body:
%y = add i32 %x, 1
%helper1 = call i32 @test2_helper()
%recurse = call i32 @test2_non_constants(i32 %y)
ret i32 %helper1
return:
%helper2 = call i32 @test2_helper()
ret i32 %helper2
}
declare i32 @test2_helper()
; CHECK-LABEL: define i32 @test2_non_constants(
; CHECK: tailrecurse:
; CHECK: %ret.tr = phi i32 [ poison, %entry ], [ %current.ret.tr, %body ]
; CHECK: %ret.known.tr = phi i1 [ false, %entry ], [ true, %body ]
; CHECK: body:
; CHECK-NOT: %recurse
; CHECK: %current.ret.tr = select i1 %ret.known.tr, i32 %ret.tr, i32 %helper1
; CHECK-NOT: ret
; CHECK: return:
; CHECK: %current.ret.tr1 = select i1 %ret.known.tr, i32 %ret.tr, i32 %helper2
; CHECK: ret i32 %current.ret.tr1
define i32 @test3_mixed(i32 %x) {
entry:
switch i32 %x, label %default [
i32 0, label %case0
i32 1, label %case1
i32 2, label %case2
]
case0:
%helper1 = call i32 @test3_helper()
br label %return
case1:
%y1 = add i32 %x, -1
%recurse1 = call i32 @test3_mixed(i32 %y1)
br label %return
case2:
%y2 = add i32 %x, -1
%helper2 = call i32 @test3_helper()
%recurse2 = call i32 @test3_mixed(i32 %y2)
br label %return
default:
%y3 = urem i32 %x, 3
%recurse3 = call i32 @test3_mixed(i32 %y3)
br label %return
return:
%retval = phi i32 [ %recurse3, %default ], [ %helper2, %case2 ], [ 9, %case1 ], [ %helper1, %case0 ]
ret i32 %retval
}
declare i32 @test3_helper()
; CHECK-LABEL: define i32 @test3_mixed(
; CHECK: tailrecurse:
; CHECK: %ret.tr = phi i32 [ poison, %entry ], [ %current.ret.tr, %case1 ], [ %current.ret.tr1, %case2 ], [ %ret.tr, %default ]
; CHECK: %ret.known.tr = phi i1 [ false, %entry ], [ true, %case1 ], [ true, %case2 ], [ %ret.known.tr, %default ]
; CHECK: case1:
; CHECK-NOT: %recurse
; CHECK: %current.ret.tr = select i1 %ret.known.tr, i32 %ret.tr, i32 9
; CHECK: br label %tailrecurse
; CHECK: case2:
; CHECK-NOT: %recurse
; CHECK: %current.ret.tr1 = select i1 %ret.known.tr, i32 %ret.tr, i32 %helper2
; CHECK: br label %tailrecurse
; CHECK: default:
; CHECK-NOT: %recurse
; CHECK: br label %tailrecurse
; CHECK: return:
; CHECK: %current.ret.tr2 = select i1 %ret.known.tr, i32 %ret.tr, i32 %helper1
; CHECK: ret i32 %current.ret.tr2
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