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| ; RUN: opt -S -simplifycfg < %s | FileCheck %s
; SimplifyCFG should eliminate redundant indirectbr edges.
; CHECK: indbrtest0
; CHECK: indirectbr i8* %t, [label %BB0, label %BB1, label %BB2]
; CHECK: %x = phi i32 [ 0, %BB0 ], [ 1, %entry ]
declare void @foo()
declare void @A()
declare void @B(i32)
declare void @C()
define void @indbrtest0(i8** %P, i8** %Q) {
entry:
store i8* blockaddress(@indbrtest0, %BB0), i8** %P
store i8* blockaddress(@indbrtest0, %BB1), i8** %P
store i8* blockaddress(@indbrtest0, %BB2), i8** %P
call void @foo()
%t = load i8*, i8** %Q
indirectbr i8* %t, [label %BB0, label %BB1, label %BB2, label %BB0, label %BB1, label %BB2]
BB0:
call void @A()
br label %BB1
BB1:
%x = phi i32 [ 0, %BB0 ], [ 1, %entry ], [ 1, %entry ]
call void @B(i32 %x)
ret void
BB2:
call void @C()
ret void
}
; SimplifyCFG should convert the indirectbr into a directbr. It would be even
; better if it removed the branch altogether, but simplifycfdg currently misses
; that because the predecessor is the entry block.
; CHECK: indbrtest1
; CHECK: br label %BB0
define void @indbrtest1(i8** %P, i8** %Q) {
entry:
store i8* blockaddress(@indbrtest1, %BB0), i8** %P
call void @foo()
%t = load i8*, i8** %Q
indirectbr i8* %t, [label %BB0, label %BB0]
BB0:
call void @A()
ret void
}
; SimplifyCFG should notice that BB0 does not have its address taken and
; remove it from entry's successor list.
; CHECK: indbrtest2
; CHECK: entry:
; CHECK-NEXT: unreachable
define void @indbrtest2(i8* %t) {
entry:
indirectbr i8* %t, [label %BB0, label %BB0]
BB0:
ret void
}
; Make sure the blocks in the next few tests aren't trivially removable as
; successors by taking their addresses.
@anchor = constant [13 x i8*] [
i8* blockaddress(@indbrtest3, %L1), i8* blockaddress(@indbrtest3, %L2), i8* blockaddress(@indbrtest3, %L3),
i8* blockaddress(@indbrtest4, %L1), i8* blockaddress(@indbrtest4, %L2), i8* blockaddress(@indbrtest4, %L3),
i8* blockaddress(@indbrtest5, %L1), i8* blockaddress(@indbrtest5, %L2), i8* blockaddress(@indbrtest5, %L3), i8* blockaddress(@indbrtest5, %L4),
i8* blockaddress(@indbrtest6, %L1), i8* blockaddress(@indbrtest6, %L2), i8* blockaddress(@indbrtest6, %L3)
]
; SimplifyCFG should turn the indirectbr into a conditional branch on the
; condition of the select.
; CHECK-LABEL: @indbrtest3(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 %cond, label %L1, label %L2
; CHECK-NOT: indirectbr
; CHECK-NOT: br
; CHECK-NOT: L3:
define void @indbrtest3(i1 %cond, i8* %address) nounwind {
entry:
%indirect.goto.dest = select i1 %cond, i8* blockaddress(@indbrtest3, %L1), i8* blockaddress(@indbrtest3, %L2)
indirectbr i8* %indirect.goto.dest, [label %L1, label %L2, label %L3]
L1:
call void @A()
ret void
L2:
call void @C()
ret void
L3:
call void @foo()
ret void
}
; SimplifyCFG should turn the indirectbr into an unconditional branch to the
; only possible destination.
; As in @indbrtest1, it should really remove the branch entirely, but it doesn't
; because it's in the entry block.
; CHECK-LABEL: @indbrtest4(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label %L1
define void @indbrtest4(i1 %cond) nounwind {
entry:
%indirect.goto.dest = select i1 %cond, i8* blockaddress(@indbrtest4, %L1), i8* blockaddress(@indbrtest4, %L1)
indirectbr i8* %indirect.goto.dest, [label %L1, label %L2, label %L3]
L1:
call void @A()
ret void
L2:
call void @C()
ret void
L3:
call void @foo()
ret void
}
; SimplifyCFG should turn the indirectbr into an unreachable because neither
; destination is listed as a successor.
; CHECK-LABEL: @indbrtest5(
; CHECK-NEXT: entry:
; CHECK-NEXT: unreachable
; CHECK-NEXT: }
define void @indbrtest5(i1 %cond, i8* %anchor) nounwind {
entry:
%indirect.goto.dest = select i1 %cond, i8* blockaddress(@indbrtest5, %L1), i8* blockaddress(@indbrtest5, %L2)
; This needs to have more than one successor for this test, otherwise it gets
; replaced with an unconditional branch to the single successor.
indirectbr i8* %indirect.goto.dest, [label %L3, label %L4]
L1:
call void @A()
ret void
L2:
call void @C()
ret void
L3:
call void @foo()
ret void
L4:
call void @foo()
; This keeps blockaddresses not otherwise listed as successors from being zapped
; before SimplifyCFG even looks at the indirectbr.
indirectbr i8* %anchor, [label %L1, label %L2]
}
; The same as above, except the selected addresses are equal.
; CHECK-LABEL: @indbrtest6(
; CHECK-NEXT: entry:
; CHECK-NEXT: unreachable
; CHECK-NEXT: }
define void @indbrtest6(i1 %cond, i8* %anchor) nounwind {
entry:
%indirect.goto.dest = select i1 %cond, i8* blockaddress(@indbrtest6, %L1), i8* blockaddress(@indbrtest6, %L1)
; This needs to have more than one successor for this test, otherwise it gets
; replaced with an unconditional branch to the single successor.
indirectbr i8* %indirect.goto.dest, [label %L2, label %L3]
L1:
call void @A()
ret void
L2:
call void @C()
ret void
L3:
call void @foo()
; This keeps blockaddresses not otherwise listed as successors from being zapped
; before SimplifyCFG even looks at the indirectbr.
indirectbr i8* %anchor, [label %L1, label %L2]
}
; PR10072
@xblkx.bbs = internal unnamed_addr constant [9 x i8*] [i8* blockaddress(@indbrtest7, %xblkx.begin), i8* blockaddress(@indbrtest7, %xblkx.begin3), i8* blockaddress(@indbrtest7, %xblkx.begin4), i8* blockaddress(@indbrtest7, %xblkx.begin5), i8* blockaddress(@indbrtest7, %xblkx.begin6), i8* blockaddress(@indbrtest7, %xblkx.begin7), i8* blockaddress(@indbrtest7, %xblkx.begin8), i8* blockaddress(@indbrtest7, %xblkx.begin9), i8* blockaddress(@indbrtest7, %xblkx.end)]
define void @indbrtest7() {
escape-string.top:
%xval202x = call i32 @xfunc5x()
br label %xlab5x
xlab8x: ; preds = %xlab5x
%xvaluex = call i32 @xselectorx()
%xblkx.x = getelementptr [9 x i8*], [9 x i8*]* @xblkx.bbs, i32 0, i32 %xvaluex
%xblkx.load = load i8*, i8** %xblkx.x
indirectbr i8* %xblkx.load, [label %xblkx.begin, label %xblkx.begin3, label %xblkx.begin4, label %xblkx.begin5, label %xblkx.begin6, label %xblkx.begin7, label %xblkx.begin8, label %xblkx.begin9, label %xblkx.end]
xblkx.begin:
br label %xblkx.end
xblkx.begin3:
br label %xblkx.end
xblkx.begin4:
br label %xblkx.end
xblkx.begin5:
br label %xblkx.end
xblkx.begin6:
br label %xblkx.end
xblkx.begin7:
br label %xblkx.end
xblkx.begin8:
br label %xblkx.end
xblkx.begin9:
br label %xblkx.end
xblkx.end:
%yes.0 = phi i1 [ false, %xblkx.begin ], [ true, %xlab8x ], [ false, %xblkx.begin9 ], [ false, %xblkx.begin8 ], [ false, %xblkx.begin7 ], [ false, %xblkx.begin6 ], [ false, %xblkx.begin5 ], [ true, %xblkx.begin4 ], [ false, %xblkx.begin3 ]
br i1 %yes.0, label %v2j, label %xlab17x
v2j:
; CHECK: %xunusedx = call i32 @xactionx()
%xunusedx = call i32 @xactionx()
br label %xlab4x
xlab17x:
br label %xlab4x
xlab4x:
%incr19 = add i32 %xval704x.0, 1
br label %xlab5x
xlab5x:
%xval704x.0 = phi i32 [ 0, %escape-string.top ], [ %incr19, %xlab4x ]
%xval10x = icmp ult i32 %xval704x.0, %xval202x
br i1 %xval10x, label %xlab8x, label %xlab9x
xlab9x:
ret void
}
declare i32 @xfunc5x()
declare i8 @xfunc7x()
declare i32 @xselectorx()
declare i32 @xactionx()
|