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| ; RUN: llc < %s -mtriple=arm-apple-darwin -relocation-model=dynamic-no-pic -mcpu=cortex-a8 -asm-verbose=false | FileCheck %s
declare void @bar(i32)
declare void @car(i32)
declare void @dar(i32)
declare void @ear(i32)
declare void @far(i32)
declare i1 @qux()
@GHJK = global i32 0
declare i8* @choose(i8*, i8*)
; BranchFolding should tail-duplicate the indirect jump to avoid
; redundant branching.
; CHECK-LABEL: tail_duplicate_me:
; CHECK: qux
; CHECK: movw r{{[0-9]+}}, :lower16:_GHJK
; CHECK: movt r{{[0-9]+}}, :upper16:_GHJK
; CHECK: str r
; CHECK-NEXT: bx r
; CHECK: qux
; CHECK: movw r{{[0-9]+}}, :lower16:_GHJK
; CHECK: movt r{{[0-9]+}}, :upper16:_GHJK
; CHECK: str r
; CHECK-NEXT: bx r
; CHECK: movw r{{[0-9]+}}, :lower16:_GHJK
; CHECK: movt r{{[0-9]+}}, :upper16:_GHJK
; CHECK: str r
; CHECK-NEXT: bx r
define void @tail_duplicate_me() nounwind {
entry:
%a = call i1 @qux()
%c = call i8* @choose(i8* blockaddress(@tail_duplicate_me, %return),
i8* blockaddress(@tail_duplicate_me, %altret))
br i1 %a, label %A, label %next
next:
%b = call i1 @qux()
br i1 %b, label %B, label %C
A:
call void @bar(i32 0)
store i32 0, i32* @GHJK
br label %M
B:
call void @car(i32 1)
store i32 0, i32* @GHJK
br label %M
C:
call void @dar(i32 2)
store i32 0, i32* @GHJK
br label %M
M:
indirectbr i8* %c, [label %return, label %altret]
return:
call void @ear(i32 1000)
ret void
altret:
call void @far(i32 1001)
ret void
}
; Use alternating abort functions so that the blocks we wish to merge are not
; layout successors during branch folding.
; CHECK-LABEL: merge_alternating_aborts:
; CHECK-NOT: _abort
; CHECK-NOT: _alt_abort
; CHECK: bxne lr
; CHECK-NOT: _abort
; CHECK-NOT: _alt_abort
; CHECK: LBB{{.*}}:
; CHECK: mov lr, pc
; CHECK: b _alt_abort
; CHECK-NOT: _abort
; CHECK-NOT: _alt_abort
; CHECK: LBB{{.*}}:
; CHECK: mov lr, pc
; CHECK: b _abort
; CHECK-NOT: _abort
; CHECK-NOT: _alt_abort
declare void @abort()
declare void @alt_abort()
define void @merge_alternating_aborts() {
entry:
%c1 = call i1 @qux()
br i1 %c1, label %cont1, label %abort1
abort1:
call void @abort()
unreachable
cont1:
%c2 = call i1 @qux()
br i1 %c2, label %cont2, label %abort2
abort2:
call void @alt_abort()
unreachable
cont2:
%c3 = call i1 @qux()
br i1 %c3, label %cont3, label %abort3
abort3:
call void @abort()
unreachable
cont3:
%c4 = call i1 @qux()
br i1 %c4, label %cont4, label %abort4
abort4:
call void @alt_abort()
unreachable
cont4:
ret void
}
|