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 } 60
