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; RUN: opt -S -passes='function(lower-expect),strip-dead-prototypes' -likely-branch-weight=2147483647 -unlikely-branch-weight=1 < %s | FileCheck %s
; The C case
; if (__builtin_expect_with_probability(((a0 == 1) || (a1 == 1) || (a2 == 1)), 1, 0))
; For the above case, all 3 branches should be annotated
; which should be equivalent to if (__builtin_expect(((a0 == 1) || (a1 == 1) || (a2 == 1)), 0))
; The C case
; if (__builtin_expect_with_probability(((a0 == 1) || (a1 == 1) || (a2 == 1)), 1, 1))
; For the above case, we do not have enough information, so only the last branch could be annotated
; which should be equivalent to if (__builtin_expect(((a0 == 1) || (a1 == 1) || (a2 == 1)), 1))
declare void @foo()
declare i64 @llvm.expect.i64(i64, i64) nounwind readnone
declare i64 @llvm.expect.with.probability.i64(i64, i64, double) nounwind readnone
; CHECK-LABEL: @test1_expect_1(
; CHECK: block0:
; CHECK-NOT: prof
; CHECK: block1:
; CHECK-NOT: prof
; CHECK: block3:
; CHECK: br i1 %tobool, label %block4, label %block5, !prof !0
define void @test1_expect_1(i8 %a0, i8 %a1, i8 %a2) {
block0:
%c0 = icmp eq i8 %a0, 1
br i1 %c0, label %block3, label %block1
block1:
%c1 = icmp eq i8 %a1, 1
br i1 %c1, label %block3, label %block2
block2:
%c2 = icmp eq i8 %a2, 1
br label %block3
block3:
%cond0 = phi i1 [ true, %block0 ], [ true, %block1 ], [ %c2, %block2 ]
%cond1 = zext i1 %cond0 to i32
%cond2 = sext i32 %cond1 to i64
%expval = call i64 @llvm.expect.i64(i64 %cond2, i64 1)
%tobool = icmp ne i64 %expval, 0
br i1 %tobool, label %block4, label %block5
block4:
call void @foo()
br label %block5
block5:
ret void
}
; should have exactly the same behavior as test1
; CHECK-LABEL: @test2_expect_with_prob_1_1(
; CHECK: block0:
; CHECK-NOT: prof
; CHECK: block1:
; CHECK-NOT: prof
; CHECK: block3:
; CHECK: br i1 %tobool, label %block4, label %block5, !prof !0
define void @test2_expect_with_prob_1_1(i8 %a0, i8 %a1, i8 %a2) {
block0:
%c0 = icmp eq i8 %a0, 1
br i1 %c0, label %block3, label %block1
block1:
%c1 = icmp eq i8 %a1, 1
br i1 %c1, label %block3, label %block2
block2:
%c2 = icmp eq i8 %a2, 1
br label %block3
block3:
%cond0 = phi i1 [ true, %block0 ], [ true, %block1 ], [ %c2, %block2 ]
%cond1 = zext i1 %cond0 to i32
%cond2 = sext i32 %cond1 to i64
%expval = call i64 @llvm.expect.with.probability.i64(i64 %cond2, i64 1, double 1.0)
%tobool = icmp ne i64 %expval, 0
br i1 %tobool, label %block4, label %block5
block4:
call void @foo()
br label %block5
block5:
ret void
}
; should have exactly the same behavior as test1
; CHECK-LABEL: @test3_expect_with_prob_0_0(
; CHECK: block0:
; CHECK-NOT: prof
; CHECK: block1:
; CHECK-NOT: prof
; CHECK: block3:
; CHECK: br i1 %tobool, label %block4, label %block5, !prof !0
define void @test3_expect_with_prob_0_0(i8 %a0, i8 %a1, i8 %a2) {
block0:
%c0 = icmp eq i8 %a0, 1
br i1 %c0, label %block3, label %block1
block1:
%c1 = icmp eq i8 %a1, 1
br i1 %c1, label %block3, label %block2
block2:
%c2 = icmp eq i8 %a2, 1
br label %block3
block3:
%cond0 = phi i1 [ true, %block0 ], [ true, %block1 ], [ %c2, %block2 ]
%cond1 = zext i1 %cond0 to i32
%cond2 = sext i32 %cond1 to i64
%expval = call i64 @llvm.expect.with.probability.i64(i64 %cond2, i64 0, double 0.0)
%tobool = icmp ne i64 %expval, 0
br i1 %tobool, label %block4, label %block5
block4:
call void @foo()
br label %block5
block5:
ret void
}
; CHECK-LABEL: @test4_expect_0(
; CHECK: block0:
; CHECK: br i1 %c0, label %block3, label %block1, !prof !1
; CHECK: block1:
; CHECK: br i1 %c1, label %block3, label %block2, !prof !1
; CHECK: block3:
; CHECK: br i1 %tobool, label %block4, label %block5, !prof !1
define void @test4_expect_0(i8 %a0, i8 %a1, i8 %a2) {
block0:
%c0 = icmp eq i8 %a0, 1
br i1 %c0, label %block3, label %block1
block1:
%c1 = icmp eq i8 %a1, 1
br i1 %c1, label %block3, label %block2
block2:
%c2 = icmp eq i8 %a2, 1
br label %block3
block3:
%cond0 = phi i1 [ true, %block0 ], [ true, %block1 ], [ %c2, %block2 ]
%cond1 = zext i1 %cond0 to i32
%cond2 = sext i32 %cond1 to i64
%expval = call i64 @llvm.expect.i64(i64 %cond2, i64 0)
%tobool = icmp ne i64 %expval, 0
br i1 %tobool, label %block4, label %block5
block4:
call void @foo()
br label %block5
block5:
ret void
}
; should have exactly the same behavior as test4
; CHECK-LABEL: @test5_expect_with_prob_1_0(
; CHECK: block0:
; CHECK: br i1 %c0, label %block3, label %block1, !prof !1
; CHECK: block1:
; CHECK: br i1 %c1, label %block3, label %block2, !prof !1
; CHECK: block3:
; CHECK: br i1 %tobool, label %block4, label %block5, !prof !1
define void @test5_expect_with_prob_1_0(i8 %a0, i8 %a1, i8 %a2) {
block0:
%c0 = icmp eq i8 %a0, 1
br i1 %c0, label %block3, label %block1
block1:
%c1 = icmp eq i8 %a1, 1
br i1 %c1, label %block3, label %block2
block2:
%c2 = icmp eq i8 %a2, 1
br label %block3
block3:
%cond0 = phi i1 [ true, %block0 ], [ true, %block1 ], [ %c2, %block2 ]
%cond1 = zext i1 %cond0 to i32
%cond2 = sext i32 %cond1 to i64
%expval = call i64 @llvm.expect.with.probability.i64(i64 %cond2, i64 1, double 0.0)
%tobool = icmp ne i64 %expval, 0
br i1 %tobool, label %block4, label %block5
block4:
call void @foo()
br label %block5
block5:
ret void
}
; should have exactly the same behavior as test4
; CHECK-LABEL: @test6_expect_with_prob_0_1(
; CHECK: block0:
; CHECK: br i1 %c0, label %block3, label %block1, !prof !1
; CHECK: block1:
; CHECK: br i1 %c1, label %block3, label %block2, !prof !1
; CHECK: block3:
; CHECK: br i1 %tobool, label %block4, label %block5, !prof !1
define void @test6_expect_with_prob_0_1(i8 %a0, i8 %a1, i8 %a2) {
block0:
%c0 = icmp eq i8 %a0, 1
br i1 %c0, label %block3, label %block1
block1:
%c1 = icmp eq i8 %a1, 1
br i1 %c1, label %block3, label %block2
block2:
%c2 = icmp eq i8 %a2, 1
br label %block3
block3:
%cond0 = phi i1 [ true, %block0 ], [ true, %block1 ], [ %c2, %block2 ]
%cond1 = zext i1 %cond0 to i32
%cond2 = sext i32 %cond1 to i64
%expval = call i64 @llvm.expect.with.probability.i64(i64 %cond2, i64 0, double 1.0)
%tobool = icmp ne i64 %expval, 0
br i1 %tobool, label %block4, label %block5
block4:
call void @foo()
br label %block5
block5:
ret void
}
; CHECK: !0 = !{!"branch_weights", !"expected", i32 2147483647, i32 1}
; CHECK: !1 = !{!"branch_weights", !"expected", i32 1, i32 2147483647}
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