| Eli Friedman | 9a46815 | 2011-08-17 22:22:24 +0000 | [diff] [blame] | 1 | ; RUN: opt -basicaa -dse -S < %s | FileCheck %s |
| 2 | |
| 3 | target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64" |
| 4 | target triple = "x86_64-apple-macosx10.7.0" |
| 5 | |
| 6 | ; Sanity tests for atomic stores. |
| 7 | ; Note that it turns out essentially every transformation DSE does is legal on |
| 8 | ; atomic ops, just some transformations are not allowed across them. |
| 9 | |
| 10 | @x = common global i32 0, align 4 |
| 11 | @y = common global i32 0, align 4 |
| 12 | |
| 13 | declare void @randomop(i32*) |
| 14 | |
| 15 | ; DSE across unordered store (allowed) |
| 16 | define void @test1() nounwind uwtable ssp { |
| 17 | ; CHECK: test1 |
| 18 | ; CHECK-NOT: store i32 0 |
| 19 | ; CHECK: store i32 1 |
| 20 | entry: |
| 21 | store i32 0, i32* @x |
| 22 | store atomic i32 0, i32* @y unordered, align 4 |
| 23 | store i32 1, i32* @x |
| 24 | ret void |
| 25 | } |
| 26 | |
| 27 | ; DSE across seq_cst load (allowed in theory; not implemented ATM) |
| 28 | define i32 @test2() nounwind uwtable ssp { |
| 29 | ; CHECK: test2 |
| 30 | ; CHECK: store i32 0 |
| 31 | ; CHECK: store i32 1 |
| 32 | entry: |
| 33 | store i32 0, i32* @x |
| 34 | %x = load atomic i32* @y seq_cst, align 4 |
| 35 | store i32 1, i32* @x |
| 36 | ret i32 %x |
| 37 | } |
| 38 | |
| 39 | ; DSE across seq_cst store (store before atomic store must not be removed) |
| 40 | define void @test3() nounwind uwtable ssp { |
| 41 | ; CHECK: test3 |
| 42 | ; CHECK: store i32 |
| 43 | ; CHECK: store atomic i32 2 |
| 44 | entry: |
| 45 | store i32 0, i32* @x |
| 46 | store atomic i32 2, i32* @y seq_cst, align 4 |
| 47 | store i32 1, i32* @x |
| 48 | ret void |
| 49 | } |
| 50 | |
| 51 | ; DSE remove unordered store (allowed) |
| 52 | define void @test4() nounwind uwtable ssp { |
| 53 | ; CHECK: test4 |
| 54 | ; CHECK-NOT: store atomic |
| 55 | ; CHECK: store i32 1 |
| 56 | entry: |
| 57 | store atomic i32 0, i32* @x unordered, align 4 |
| 58 | store i32 1, i32* @x |
| 59 | ret void |
| 60 | } |
| 61 | |
| 62 | ; DSE unordered store overwriting non-atomic store (allowed) |
| 63 | define void @test5() nounwind uwtable ssp { |
| 64 | ; CHECK: test5 |
| 65 | ; CHECK: store atomic i32 1 |
| 66 | entry: |
| 67 | store i32 0, i32* @x |
| 68 | store atomic i32 1, i32* @x unordered, align 4 |
| 69 | ret void |
| 70 | } |
| 71 | |
| 72 | ; DSE no-op unordered atomic store (allowed) |
| 73 | define void @test6() nounwind uwtable ssp { |
| 74 | ; CHECK: test6 |
| 75 | ; CHECK-NOT: store |
| 76 | ; CHECK: ret void |
| 77 | entry: |
| 78 | %x = load atomic i32* @x unordered, align 4 |
| 79 | store atomic i32 %x, i32* @x unordered, align 4 |
| 80 | ret void |
| 81 | } |
| 82 | |
| 83 | ; DSE seq_cst store (be conservative; DSE doesn't have infrastructure |
| 84 | ; to reason about atomic operations). |
| 85 | define void @test7() nounwind uwtable ssp { |
| 86 | ; CHECK: test7 |
| 87 | ; CHECK: store atomic |
| 88 | entry: |
| 89 | %a = alloca i32 |
| 90 | store atomic i32 0, i32* %a seq_cst, align 4 |
| 91 | ret void |
| 92 | } |
| 93 | |
| 94 | ; DSE and seq_cst load (be conservative; DSE doesn't have infrastructure |
| 95 | ; to reason about atomic operations). |
| 96 | define i32 @test8() nounwind uwtable ssp { |
| 97 | ; CHECK: test8 |
| 98 | ; CHECK: store |
| 99 | ; CHECK: load atomic |
| 100 | entry: |
| 101 | %a = alloca i32 |
| 102 | call void @randomop(i32* %a) |
| 103 | store i32 0, i32* %a, align 4 |
| 104 | %x = load atomic i32* @x seq_cst, align 4 |
| 105 | ret i32 %x |
| 106 | } |
| 107 | |