| Matthijs Kooijman | 8f3c6ca | 2008-05-23 09:09:41 +0000 | [diff] [blame] | 1 | ; RUN: llvm-as < %s | opt -simplifycfg | llvm-dis > %t |
| 2 | ; RUN: not grep {^BB.tomerge} %t |
| 3 | ; RUN grep {^BB.nomerge} %t | count 2 |
| 4 | |
| 5 | ; ModuleID = '<stdin>' |
| 6 | declare i1 @foo() |
| 7 | |
| 8 | declare i1 @bar(i32) |
| 9 | |
| 10 | ; This function can't be merged |
| 11 | define void @a() { |
| 12 | entry: |
| 13 | br label %BB.nomerge |
| 14 | |
| 15 | BB.nomerge: ; preds = %Common, %entry |
| 16 | ; This phi has a conflicting value (0) with below phi (2), so blocks |
| 17 | ; can't be merged. |
| 18 | %a = phi i32 [ 1, %entry ], [ 0, %Common ] ; <i32> [#uses=1] |
| 19 | br label %Succ |
| 20 | |
| 21 | Succ: ; preds = %Common, %BB.nomerge |
| 22 | %b = phi i32 [ %a, %BB.nomerge ], [ 2, %Common ] ; <i32> [#uses=0] |
| 23 | %conde = call i1 @foo( ) ; <i1> [#uses=1] |
| 24 | br i1 %conde, label %Common, label %Exit |
| 25 | |
| 26 | Common: ; preds = %Succ |
| 27 | %cond = call i1 @foo( ) ; <i1> [#uses=1] |
| 28 | br i1 %cond, label %BB.nomerge, label %Succ |
| 29 | |
| 30 | Exit: ; preds = %Succ |
| 31 | ret void |
| 32 | } |
| 33 | |
| 34 | ; This function can't be merged |
| 35 | define void @b() { |
| 36 | entry: |
| 37 | br label %BB.nomerge |
| 38 | |
| 39 | BB.nomerge: ; preds = %Common, %entry |
| 40 | br label %Succ |
| 41 | |
| 42 | Succ: ; preds = %Common, %BB.nomerge |
| 43 | ; This phi has confliction values for Common and (through BB) Common, |
| 44 | ; blocks can't be merged |
| 45 | %b = phi i32 [ 1, %BB.nomerge ], [ 2, %Common ] ; <i32> [#uses=0] |
| 46 | %conde = call i1 @foo( ) ; <i1> [#uses=1] |
| 47 | br i1 %conde, label %Common, label %Exit |
| 48 | |
| 49 | Common: ; preds = %Succ |
| 50 | %cond = call i1 @foo( ) ; <i1> [#uses=1] |
| 51 | br i1 %cond, label %BB.nomerge, label %Succ |
| 52 | |
| 53 | Exit: ; preds = %Succ |
| 54 | ret void |
| 55 | } |
| 56 | |
| 57 | ; This function can be merged |
| 58 | define void @c() { |
| 59 | entry: |
| 60 | br label %BB.tomerge |
| 61 | |
| 62 | BB.tomerge: ; preds = %Common, %entry |
| 63 | br label %Succ |
| 64 | |
| 65 | Succ: ; preds = %Common, %BB.tomerge, %Pre-Exit |
| 66 | ; This phi has identical values for Common and (through BB) Common, |
| 67 | ; blocks can't be merged |
| 68 | %b = phi i32 [ 1, %BB.tomerge ], [ 1, %Common ], [ 2, %Pre-Exit ] |
| 69 | %conde = call i1 @foo( ) ; <i1> [#uses=1] |
| 70 | br i1 %conde, label %Common, label %Pre-Exit |
| 71 | |
| 72 | Common: ; preds = %Succ |
| 73 | %cond = call i1 @foo( ) ; <i1> [#uses=1] |
| 74 | br i1 %cond, label %BB.tomerge, label %Succ |
| 75 | |
| 76 | Pre-Exit: ; preds = %Succ |
| 77 | ; This adds a backedge, so the %b phi node gets a third branch and is |
| 78 | ; not completely trivial |
| 79 | %cond2 = call i1 @foo( ) ; <i1> [#uses=1] |
| 80 | br i1 %cond2, label %Succ, label %Exit |
| 81 | |
| 82 | Exit: ; preds = %Pre-Exit |
| 83 | ret void |
| 84 | } |
| 85 | |
| 86 | ; This function can be merged |
| 87 | define void @d() { |
| 88 | entry: |
| 89 | br label %BB.tomerge |
| 90 | |
| 91 | BB.tomerge: ; preds = %Common, %entry |
| 92 | ; This phi has a matching value (0) with below phi (0), so blocks |
| 93 | ; can be merged. |
| 94 | %a = phi i32 [ 1, %entry ], [ 0, %Common ] ; <i32> [#uses=1] |
| 95 | br label %Succ |
| 96 | |
| 97 | Succ: ; preds = %Common, %BB.tomerge |
| 98 | %b = phi i32 [ %a, %BB.tomerge ], [ 0, %Common ] ; <i32> [#uses=0] |
| 99 | %conde = call i1 @foo( ) ; <i1> [#uses=1] |
| 100 | br i1 %conde, label %Common, label %Exit |
| 101 | |
| 102 | Common: ; preds = %Succ |
| 103 | %cond = call i1 @foo( ) ; <i1> [#uses=1] |
| 104 | br i1 %cond, label %BB.tomerge, label %Succ |
| 105 | |
| 106 | Exit: ; preds = %Succ |
| 107 | ret void |
| 108 | } |
| 109 | |
| 110 | ; This function can be merged |
| 111 | define void @e() { |
| 112 | entry: |
| 113 | br label %BB.tomerge |
| 114 | |
| 115 | BB.tomerge: ; preds = %Use, %entry |
| 116 | ; This phi is used somewhere else than Succ, but this should not prevent |
| 117 | ; merging this block |
| 118 | %a = phi i32 [ 1, %entry ], [ 0, %Use ] ; <i32> [#uses=1] |
| 119 | br label %Succ |
| 120 | |
| 121 | Succ: ; preds = %BB.tomerge |
| 122 | %conde = call i1 @foo( ) ; <i1> [#uses=1] |
| 123 | br i1 %conde, label %Use, label %Exit |
| 124 | |
| 125 | Use: ; preds = %Succ |
| 126 | %cond = call i1 @bar( i32 %a ) ; <i1> [#uses=1] |
| 127 | br i1 %cond, label %BB.tomerge, label %Exit |
| 128 | |
| 129 | Exit: ; preds = %Use, %Succ |
| 130 | ret void |
| 131 | } |