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; RUN: llc -mtriple=i686-pc-gnu-linux < %s | FileCheck %s -check-prefix=CHECK
; RUN: llc -mtriple=i686-pc-gnu-linux -print-machineinstrs=expand-isel-pseudos %s -o /dev/null 2>&1 | FileCheck %s -check-prefix=CHECK-JT-WEIGHT
; An unreachable default destination is replaced with the most popular case label.
define void @foo(i32 %x, i32* %to) {
; CHECK-LABEL: foo:
; CHECK: movl 4(%esp), [[REG:%e[a-z]{2}]]
; CHECK: cmpl $3, [[REG]]
; CHECK: ja .LBB0_6
; CHECK-NEXT: # BB#1:
; CHECK-NEXT: jmpl *.LJTI0_0(,[[REG]],4)
; CHECK: movl $4
; CHECK: retl
entry:
switch i32 %x, label %default [
i32 0, label %bb0
i32 1, label %bb1
i32 2, label %bb2
i32 3, label %bb3
i32 4, label %bb4
i32 5, label %bb4
]
bb0:
store i32 0, i32* %to
br label %exit
bb1:
store i32 1, i32* %to
br label %exit
bb2:
store i32 2, i32* %to
br label %exit
bb3:
store i32 3, i32* %to
br label %exit
bb4:
store i32 4, i32* %to
br label %exit
exit:
ret void
default:
unreachable
; The jump table has four entries.
; CHECK-LABEL: .LJTI0_0:
; CHECK-NEXT: .long .LBB0_2
; CHECK-NEXT: .long .LBB0_3
; CHECK-NEXT: .long .LBB0_4
; CHECK-NEXT: .long .LBB0_5
}
; Check if branch probabilities are correctly assigned to the jump table.
define void @bar(i32 %x, i32* %to) {
; CHECK-JT-WEIGHT-LABEL: bar:
; CHECK-JT-WEIGHT: Successors according to CFG: BB#6(16) BB#8(96)
; CHECK-JT-WEIGHT: Successors according to CFG: BB#1(16) BB#2(16) BB#3(16) BB#4(16) BB#5(32)
entry:
switch i32 %x, label %default [
i32 0, label %bb0
i32 1, label %bb1
i32 2, label %bb2
i32 3, label %bb3
i32 4, label %bb4
i32 5, label %bb4
], !prof !1
bb0:
store i32 0, i32* %to
br label %exit
bb1:
store i32 1, i32* %to
br label %exit
bb2:
store i32 2, i32* %to
br label %exit
bb3:
store i32 3, i32* %to
br label %exit
bb4:
store i32 4, i32* %to
br label %exit
default:
store i32 5, i32* %to
br label %exit
exit:
ret void
}
!1 = !{!"branch_weights", i32 16, i32 16, i32 16, i32 16, i32 16, i32 16, i32 16}
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