MachineBranchProb.ll
2.26 KB
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; RUN: llc < %s -print-after=finalize-isel -o /dev/null 2>&1 | FileCheck %s
; Hexagon runs passes that renumber the basic blocks, causing this test
; to fail.
; XFAIL: hexagon
declare void @foo()
; Make sure we have the correct weight attached to each successor.
define i32 @test2(i32 %x) nounwind uwtable readnone ssp {
; CHECK-LABEL: Machine code for function test2:
entry:
%conv = sext i32 %x to i64
switch i64 %conv, label %return [
i64 0, label %sw.bb
i64 1, label %sw.bb
i64 4, label %sw.bb
i64 5, label %sw.bb1
i64 15, label %sw.bb
], !prof !0
; CHECK: bb.0.entry:
; CHECK: successors: %bb.1(0x75f8ebf2), %bb.4(0x0a07140e)
; CHECK: bb.4.entry:
; CHECK: successors: %bb.2(0x60606068), %bb.5(0x1f9f9f98)
; CHECK: bb.5.entry:
; CHECK: successors: %bb.1(0x3cf3cf4b), %bb.6(0x430c30b5)
; CHECK: bb.6.entry:
; CHECK: successors: %bb.1(0x2e8ba2d7), %bb.3(0x51745d29)
sw.bb:
; this call will prevent simplifyCFG from optimizing the block away in ARM/AArch64.
tail call void @foo()
br label %return
sw.bb1:
br label %return
return:
%retval.0 = phi i32 [ 5, %sw.bb1 ], [ 1, %sw.bb ], [ 0, %entry ]
ret i32 %retval.0
}
!0 = !{!"branch_weights", i32 7, i32 6, i32 4, i32 4, i32 64, i21 1000}
declare void @g(i32)
define void @left_leaning_weight_balanced_tree(i32 %x) {
entry:
switch i32 %x, label %return [
i32 0, label %bb0
i32 100, label %bb1
i32 200, label %bb2
i32 300, label %bb3
i32 400, label %bb4
i32 500, label %bb5
], !prof !1
bb0: tail call void @g(i32 0) br label %return
bb1: tail call void @g(i32 1) br label %return
bb2: tail call void @g(i32 2) br label %return
bb3: tail call void @g(i32 3) br label %return
bb4: tail call void @g(i32 4) br label %return
bb5: tail call void @g(i32 5) br label %return
return: ret void
; Check that we set branch weights on the pivot cmp instruction correctly.
; Cases {0,100,200,300} go on the left with weight 13; cases {400,500} go on the
; right with weight 20.
;
; CHECK-LABEL: Machine code for function left_leaning_weight_balanced_tree:
; CHECK: bb.0.entry:
; CHECK-NOT: Successors
; CHECK: successors: %bb.8(0x32d2d2d3), %bb.9(0x4d2d2d2d)
}
!1 = !{!"branch_weights",
; Default:
i32 1,
; Case 0, 100, 200:
i32 10, i32 1, i32 1,
; Case 300, 400, 500:
i32 1, i32 10, i32 10}