; RUN: llc < %s -mtriple=thumbv7-apple-ios -mcpu=cortex-a9 -jump-table-density=40 | FileCheck %s ; Test that ldmia_ret preserves implicit operands for return values. ; ; This CFG is reduced from a benchmark miscompile. With current ; if-conversion heuristics, one of the return paths is if-converted ; into sw.bb18 resulting in an ldmia_ret in the middle of the ; block. The postra scheduler needs to know that the return implicitly ; uses the return register, otherwise its antidep breaker scavenges ; the register in order to hoist the constant load required to test ; the switch. declare i32 @getint() declare i1 @getbool() declare void @foo(i32) declare i32 @bar(i32) define i32 @test(i32 %in1, i32 %in2) nounwind { entry: %call = tail call zeroext i1 @getbool() nounwind br i1 %call, label %sw.bb18, label %sw.bb2 sw.bb2: ; preds = %entry %cmp = tail call zeroext i1 @getbool() nounwind br i1 %cmp, label %sw.epilog58, label %land.lhs.true land.lhs.true: ; preds = %sw.bb2 %cmp13 = tail call zeroext i1 @getbool() nounwind br i1 %cmp13, label %if.then, label %sw.epilog58 if.then: ; preds = %land.lhs.true tail call void @foo(i32 %in1) nounwind br label %sw.epilog58 ; load the return value ; CHECK: movs [[RRET:r.]], #2 ; hoist the switch constant without clobbering RRET ; CHECK: movw ; CHECK-NOT: [[RRET]] ; CHECK: , #63707 ; CHECK-NOT: [[RRET]] ; CHECK: tst ; If-convert the return ; CHECK: it ne ; Fold the CSR+return into a pop ; CHECK: pop {r4, r5, r7, pc} sw.bb18: %call20 = tail call i32 @bar(i32 %in2) nounwind switch i32 %call20, label %sw.default56 [ i32 168, label %sw.bb21 i32 165, label %sw.bb21 i32 261, label %sw.epilog58 i32 188, label %sw.epilog58 i32 187, label %sw.epilog58 i32 186, label %sw.epilog58 i32 185, label %sw.epilog58 i32 184, label %sw.epilog58 i32 175, label %sw.epilog58 i32 174, label %sw.epilog58 i32 173, label %sw.epilog58 i32 172, label %sw.epilog58 i32 171, label %sw.epilog58 i32 167, label %sw.epilog58 i32 166, label %sw.epilog58 i32 164, label %sw.epilog58 i32 163, label %sw.epilog58 i32 161, label %sw.epilog58 i32 160, label %sw.epilog58 i32 -1, label %sw.bb33 ] sw.bb21: ; preds = %sw.bb18, %sw.bb18 tail call void @foo(i32 %in2) nounwind %call28 = tail call i32 @getint() nounwind %tobool = icmp eq i32 %call28, 0 br i1 %tobool, label %if.then29, label %sw.epilog58 if.then29: ; preds = %sw.bb21 tail call void @foo(i32 %in2) nounwind br label %sw.epilog58 sw.bb33: ; preds = %sw.bb18 %cmp42 = tail call zeroext i1 @getbool() nounwind br i1 %cmp42, label %sw.default56, label %land.lhs.true44 land.lhs.true44: ; preds = %sw.bb33 %call50 = tail call i32 @getint() nounwind %cmp51 = icmp slt i32 %call50, 0 br i1 %cmp51, label %if.then53, label %sw.default56 if.then53: ; preds = %land.lhs.true44 tail call void @foo(i32 %in2) nounwind br label %sw.default56 sw.default56: ; preds = %sw.bb33, %land.lhs.true44, %if.then53, %sw.bb18 br label %sw.epilog58 sw.epilog58: %retval.0 = phi i32 [ 4, %sw.default56 ], [ 2, %sw.bb21 ], [ 2, %if.then29 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb18 ], [ 2, %sw.bb2 ], [ 2, %land.lhs.true ], [ 2, %if.then ] ret i32 %retval.0 }