| Dan Gohman | 0a6021a | 2010-11-10 20:37:15 +0000 | [diff] [blame] | 1 | ; RUN: opt -basicaa -gvn -S < %s | FileCheck %s |
| 2 | |
| 3 | target datalayout = "e-p:64:64:64" |
| 4 | |
| 5 | ; GVN should ignore the store to p[1] to see that the load from p[0] is |
| 6 | ; fully redundant. |
| 7 | |
| 8 | ; CHECK: @yes |
| 9 | ; CHECK: if.then: |
| 10 | ; CHECK-NEXT: store i32 0, i32* %q |
| 11 | ; CHECK-NEXT: ret void |
| 12 | |
| 13 | define void @yes(i1 %c, i32* %p, i32* %q) nounwind { |
| 14 | entry: |
| 15 | store i32 0, i32* %p |
| 16 | %p1 = getelementptr inbounds i32* %p, i64 1 |
| 17 | store i32 1, i32* %p1 |
| 18 | br i1 %c, label %if.else, label %if.then |
| 19 | |
| 20 | if.then: |
| 21 | %t = load i32* %p |
| 22 | store i32 %t, i32* %q |
| 23 | ret void |
| 24 | |
| 25 | if.else: |
| 26 | ret void |
| 27 | } |
| 28 | |
| 29 | ; GVN should ignore the store to p[1] to see that the first load from p[0] is |
| 30 | ; fully redundant. However, the second load is larger, so it's not a simple |
| 31 | ; redundancy. |
| 32 | |
| 33 | ; CHECK: @watch_out_for_size_change |
| 34 | ; CHECK: if.then: |
| 35 | ; CHECK-NEXT: store i32 0, i32* %q |
| 36 | ; CHECK-NEXT: ret void |
| 37 | ; CHECK: if.else: |
| 38 | ; CHECK: load i64* %pc |
| 39 | ; CHECK: store i64 |
| 40 | |
| 41 | define void @watch_out_for_size_change(i1 %c, i32* %p, i32* %q) nounwind { |
| 42 | entry: |
| 43 | store i32 0, i32* %p |
| 44 | %p1 = getelementptr inbounds i32* %p, i64 1 |
| 45 | store i32 1, i32* %p1 |
| 46 | br i1 %c, label %if.else, label %if.then |
| 47 | |
| 48 | if.then: |
| 49 | %t = load i32* %p |
| 50 | store i32 %t, i32* %q |
| 51 | ret void |
| 52 | |
| 53 | if.else: |
| 54 | %pc = bitcast i32* %p to i64* |
| 55 | %qc = bitcast i32* %q to i64* |
| 56 | %t64 = load i64* %pc |
| 57 | store i64 %t64, i64* %qc |
| 58 | ret void |
| 59 | } |