; REQUIRES: asserts ; RUN: opt -S -passes=dfa-jump-threading -verify-dom-info=1 -debug-only=dfa-jump-threading -disable-output %s 2>&1 | FileCheck %s ; RUN: opt -S -passes=dfa-jump-threading -verify-dom-info=1 -print-prof-data %s -o - | FileCheck %s --check-prefix=PROFILE ; This test checks that the analysis identifies all threadable paths in a ; simple CFG. A threadable path includes a list of basic blocks, the exit ; state, and the block that determines the next state. ; < path of BBs that form a cycle > [ state, determinator ] define i32 @test1(i32 %num) !prof !0{ ; CHECK: < case2, for.inc, for.body > [ 1, for.inc ] ; CHECK-NEXT: < for.inc, for.body > [ 1, for.inc ] ; CHECK-NEXT: < case1, for.inc, for.body > [ 2, for.inc ] ; CHECK-NEXT: < case2, sel.si.unfold.false, for.inc, for.body > [ 2, sel.si.unfold.false ] entry: br label %for.body for.body: %count = phi i32 [ 0, %entry ], [ %inc, %for.inc ] %state = phi i32 [ 1, %entry ], [ %state.next, %for.inc ] switch i32 %state, label %for.inc [ i32 1, label %case1 i32 2, label %case2 ] case1: br label %for.inc case2: ; PROFILE-LABEL: @test1 ; PROFILE-LABEL: case2: ; PROFILE: br i1 %cmp, label %for.inc.jt1, label %sel.si.unfold.false.jt2, !prof !1 ; !1 = !{!"branch_weights", i32 3, i32 5} %cmp = icmp eq i32 %count, 50 %sel = select i1 %cmp, i32 1, i32 2, !prof !1 br label %for.inc for.inc: %state.next = phi i32 [ %sel, %case2 ], [ 1, %for.body ], [ 2, %case1 ] %inc = add nsw i32 %count, 1 %cmp.exit = icmp slt i32 %inc, %num br i1 %cmp.exit, label %for.body, label %for.end for.end: ret i32 0 } ; This test checks that the analysis finds threadable paths in a more ; complicated CFG. Here the FSM is represented as a nested loop, with ; fallthrough cases. define i32 @test2(i32 %init) { ; CHECK: < loop.1.backedge, loop.1, loop.2, loop.3 > [ 1, loop.1 ] ; CHECK-NEXT: < case4, loop.1.backedge, state.1.be2.si.unfold.false, loop.1, loop.2, loop.3 > [ 2, loop.1.backedge ] ; CHECK-NEXT: < case2, loop.1.backedge, state.1.be2.si.unfold.false, loop.1, loop.2, loop.3 > [ 4, loop.1.backedge ] ; CHECK-NEXT: < case4, loop.2.backedge, loop.2, loop.3 > [ 3, loop.2.backedge ] ; CHECK-NEXT: < case3, loop.2.backedge, loop.2, loop.3 > [ 0, loop.2.backedge ] ; CHECK-NEXT: < case2, loop.3 > [ 3, loop.3 ] entry: %cmp = icmp eq i32 %init, 0 %sel = select i1 %cmp, i32 0, i32 2 br label %loop.1 loop.1: %state.1 = phi i32 [ %sel, %entry ], [ %state.1.be2, %loop.1.backedge ] br label %loop.2 loop.2: %state.2 = phi i32 [ %state.1, %loop.1 ], [ %state.2.be, %loop.2.backedge ] br label %loop.3 loop.3: %state = phi i32 [ %state.2, %loop.2 ], [ 3, %case2 ] switch i32 %state, label %infloop.i [ i32 2, label %case2 i32 3, label %case3 i32 4, label %case4 i32 0, label %case0 i32 1, label %case1 ] case2: br i1 %cmp, label %loop.3, label %loop.1.backedge case3: br i1 %cmp, label %loop.2.backedge, label %case4 case4: br i1 %cmp, label %loop.2.backedge, label %loop.1.backedge loop.1.backedge: %state.1.be = phi i32 [ 2, %case4 ], [ 4, %case2 ] %state.1.be2 = select i1 %cmp, i32 1, i32 %state.1.be br label %loop.1 loop.2.backedge: %state.2.be = phi i32 [ 3, %case4 ], [ 0, %case3 ] br label %loop.2 case0: br label %exit case1: br label %exit infloop.i: br label %infloop.i exit: ret i32 0 } declare void @baz() ; Do not jump-thread those paths where the determinator basic block does not ; precede the basic block that defines the switch condition. ; ; Otherwise, it is possible that the state defined in the determinator block ; defines the state for the next iteration of the loop, rather than for the ; current one. define i32 @wrong_bb_order() { ; CHECK-LABEL: DFA Jump threading: wrong_bb_order ; CHECK-NOT: [ 77, bb43 ] ; CHECK-NOT: [ 77, bb43 ] bb: %i = alloca [420 x i8], align 1 %i2 = getelementptr inbounds [420 x i8], ptr %i, i64 0, i64 390 br label %bb3 bb3: ; preds = %bb59, %bb %i4 = phi ptr [ %i2, %bb ], [ %i60, %bb59 ] %i5 = phi i8 [ 77, %bb ], [ %i64, %bb59 ] %i6 = phi i32 [ 2, %bb ], [ %i63, %bb59 ] %i7 = phi i32 [ 26, %bb ], [ %i62, %bb59 ] %i8 = phi i32 [ 25, %bb ], [ %i61, %bb59 ] %i9 = icmp sgt i32 %i7, 2 %i10 = select i1 %i9, i32 %i7, i32 2 %i11 = add i32 %i8, 2 %i12 = sub i32 %i11, %i10 %i13 = mul nsw i32 %i12, 3 %i14 = add nsw i32 %i13, %i6 %i15 = sext i32 %i14 to i64 %i16 = getelementptr inbounds i8, ptr %i4, i64 %i15 %i17 = load i8, ptr %i16, align 1 %i18 = icmp sgt i8 %i17, 0 br i1 %i18, label %bb21, label %bb31 bb21: ; preds = %bb3 br i1 true, label %bb59, label %bb43 bb59: ; preds = %bb49, %bb43, %bb31, %bb21 %i60 = phi ptr [ %i44, %bb49 ], [ %i44, %bb43 ], [ %i34, %bb31 ], [ %i4, %bb21 ] %i61 = phi i32 [ %i45, %bb49 ], [ %i45, %bb43 ], [ %i33, %bb31 ], [ %i8, %bb21 ] %i62 = phi i32 [ %i47, %bb49 ], [ %i47, %bb43 ], [ %i32, %bb31 ], [ %i7, %bb21 ] %i63 = phi i32 [ %i48, %bb49 ], [ %i48, %bb43 ], [ 2, %bb31 ], [ %i6, %bb21 ] %i64 = phi i8 [ %i46, %bb49 ], [ %i46, %bb43 ], [ 77, %bb31 ], [ %i5, %bb21 ] %i65 = icmp sgt i32 %i62, 0 br i1 %i65, label %bb3, label %bb66 bb31: ; preds = %bb3 %i32 = add nsw i32 %i7, -1 %i33 = add nsw i32 %i8, -1 %i34 = getelementptr inbounds i8, ptr %i4, i64 -15 %i35 = icmp eq i8 %i5, 77 br i1 %i35, label %bb59, label %bb41 bb41: ; preds = %bb31 tail call void @baz() br label %bb43 bb43: ; preds = %bb41, %bb21 %i44 = phi ptr [ %i34, %bb41 ], [ %i4, %bb21 ] %i45 = phi i32 [ %i33, %bb41 ], [ %i8, %bb21 ] %i46 = phi i8 [ 77, %bb41 ], [ %i5, %bb21 ] %i47 = phi i32 [ %i32, %bb41 ], [ %i7, %bb21 ] %i48 = phi i32 [ 2, %bb41 ], [ %i6, %bb21 ] tail call void @baz() switch i8 %i5, label %bb59 [ i8 68, label %bb49 i8 73, label %bb49 ] bb49: ; preds = %bb43, %bb43 tail call void @baz() br label %bb59 bb66: ; preds = %bb59 ret i32 0 } ; Value %init is not predictable but it's okay since it is the value initial to the switch. define i32 @initial.value.positive1(i32 %init) !prof !0 { ; CHECK: < loop.1.backedge, loop.1, loop.2, loop.3 > [ 1, loop.1 ] ; CHECK-NEXT: < case4, loop.1.backedge, state.1.be2.si.unfold.false, loop.1, loop.2, loop.3 > [ 2, loop.1.backedge ] ; CHECK-NEXT: < case2, loop.1.backedge, state.1.be2.si.unfold.false, loop.1, loop.2, loop.3 > [ 4, loop.1.backedge ] ; CHECK-NEXT: < case4, loop.2.backedge, loop.2, loop.3 > [ 3, loop.2.backedge ] ; CHECK-NEXT: < case3, loop.2.backedge, loop.2, loop.3 > [ 0, loop.2.backedge ] ; CHECK-NEXT: < case2, loop.3 > [ 3, loop.3 ] entry: %cmp = icmp eq i32 %init, 0 br label %loop.1 loop.1: %state.1 = phi i32 [ %init, %entry ], [ %state.1.be2, %loop.1.backedge ] br label %loop.2 loop.2: %state.2 = phi i32 [ %state.1, %loop.1 ], [ %state.2.be, %loop.2.backedge ] br label %loop.3 loop.3: %state = phi i32 [ %state.2, %loop.2 ], [ 3, %case2 ] switch i32 %state, label %infloop.i [ i32 2, label %case2 i32 3, label %case3 i32 4, label %case4 i32 0, label %case0 i32 1, label %case1 ] case2: br i1 %cmp, label %loop.3, label %loop.1.backedge case3: br i1 %cmp, label %loop.2.backedge, label %case4 case4: br i1 %cmp, label %loop.2.backedge, label %loop.1.backedge loop.1.backedge: %state.1.be = phi i32 [ 2, %case4 ], [ 4, %case2 ] %state.1.be2 = select i1 %cmp, i32 1, i32 %state.1.be br label %loop.1 loop.2.backedge: %state.2.be = phi i32 [ 3, %case4 ], [ 0, %case3 ] br label %loop.2 case0: br label %exit case1: br label %exit infloop.i: br label %infloop.i exit: ret i32 0 } define i8 @cyclesInPaths1(i1 %call12, i1 %cmp18) { ; CHECK-LABEL: DFA Jump threading: cyclesInPaths1 ; CHECK-NOT: <{{.*}}> [{{.*}}] entry: br label %switchPhiDef.for.body switchPhiDef.for.body: ; preds = %detBB2, %entry %switchPhi.curState = phi i32 [ %curState.1, %detBB2 ], [ 0, %entry ] br i1 %call12, label %detBB1, label %if.else if.else: ; preds = %switchPhiDef.for.body br label %detBB1 detBB1: ; preds = %if.else, %switchPhiDef.for.body %newState.02 = phi i32 [ 2, %switchPhiDef.for.body ], [ 4, %if.else ] br i1 %cmp18, label %detBB2, label %if.end20 if.end20: ; preds = %detBB1 br i1 %call12, label %if.end23, label %switchBB switchBB: ; preds = %if.end20 switch i32 %switchPhi.curState, label %if.end23 [ i32 4, label %ret1 i32 0, label %ret2 ] ret1: ; preds = %switchBB ret i8 1 ret2: ; preds = %switchBB ret i8 2 if.end23: ; preds = %switchBB, %if.end20 br label %detBB2 detBB2: ; preds = %if.end23, %detBB1 %curState.1 = phi i32 [ %newState.02, %if.end23 ], [ 0, %detBB1 ] br label %switchPhiDef.for.body } define void @cyclesInPaths2(i1 %tobool5.not.i) { ; CHECK-LABEL: DFA Jump threading: cyclesInPaths2 ; CHECK: < sw.bb.i, bb.exit, if.end5, if.end.i > [ 1, bb.exit ] ; CHECK-NEXT: < bb.exit, if.end5, if.end.i > [ 0, bb.exit ] entry: br label %if.end5 if.end5: ; preds = %bb.exit, %entry %P.sroa.8.051 = phi i16 [ %retval.sroa.6.0.i, %bb.exit ], [ 0, %entry ] call void @foo3() br i1 %tobool5.not.i, label %if.end.i, label %bb.exit if.end.i: ; preds = %if.end5 switch i16 %P.sroa.8.051, label %sw.default.i [ i16 1, label %sw.bb.i i16 0, label %bb.exit ] sw.bb.i: ; preds = %if.end.i call void @foo1() br label %bb.exit sw.default.i: ; preds = %if.end.i unreachable bb.exit: ; preds = %sw.bb.i, %if.end.i, %if.end5 %retval.sroa.6.0.i = phi i16 [ 1, %sw.bb.i ], [ 0, %if.end5 ], [ 0, %if.end.i ] call void @foo2() br label %if.end5 } declare void @foo1() declare void @foo2() declare void @foo3() !0 = !{!"function_entry_count", i32 10} !1 = !{!"branch_weights", i32 3, i32 5}