diff options
Diffstat (limited to 'llvm/test/Transforms/CalledValuePropagation/simple-select.ll')
| -rw-r--r-- | llvm/test/Transforms/CalledValuePropagation/simple-select.ll | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/llvm/test/Transforms/CalledValuePropagation/simple-select.ll b/llvm/test/Transforms/CalledValuePropagation/simple-select.ll new file mode 100644 index 00000000000..3d6c7dad7c8 --- /dev/null +++ b/llvm/test/Transforms/CalledValuePropagation/simple-select.ll @@ -0,0 +1,39 @@ +; RUN: opt -called-value-propagation -S < %s | FileCheck %s + +target triple = "aarch64-unknown-linux-gnueabi" + +@global_function = internal unnamed_addr global void ()* null, align 8 +@global_scalar = internal unnamed_addr global i64 zeroinitializer + +; This test checks that we propagate the functions through a select +; instruction, and attach !callees metadata to the call. Such metadata can +; enable optimizations of this code sequence. +; +; For example, since both of the targeted functions have the "norecurse" +; attribute, the function attributes pass can be made to infer that +; "@test_select" is also norecurse. This would allow the globals optimizer to +; localize "@global_scalar". The function could then be further simplified to +; always return the constant "1", eliminating the load and store instructions. +; +; CHECK: call void %tmp0(), !callees ![[MD:[0-9]+]] +; CHECK: ![[MD]] = !{void ()* @norecurse_1, void ()* @norecurse_2} +; +define i64 @test_select_entry(i1 %flag) { +entry: + %tmp0 = call i64 @test_select(i1 %flag) + ret i64 %tmp0 +} + +define internal i64 @test_select(i1 %flag) { +entry: + %tmp0 = select i1 %flag, void ()* @norecurse_1, void ()* @norecurse_2 + store i64 1, i64* @global_scalar + call void %tmp0() + %tmp1 = load i64, i64* @global_scalar + ret i64 %tmp1 +} + +declare void @norecurse_1() #0 +declare void @norecurse_2() #0 + +attributes #0 = { norecurse } |
