diff options
Diffstat (limited to 'llvm/test/Feature/OperandBundles/basic-aa-argmemonly.ll')
| -rw-r--r-- | llvm/test/Feature/OperandBundles/basic-aa-argmemonly.ll | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/llvm/test/Feature/OperandBundles/basic-aa-argmemonly.ll b/llvm/test/Feature/OperandBundles/basic-aa-argmemonly.ll index 1f3b378868e..aa944588606 100644 --- a/llvm/test/Feature/OperandBundles/basic-aa-argmemonly.ll +++ b/llvm/test/Feature/OperandBundles/basic-aa-argmemonly.ll @@ -26,3 +26,26 @@ define i32 @test1(i32* %P, i32* noalias %P2) { ret i32 %diff ; CHECK: ret i32 0 } + +define i32 @test2(i32* %P, i32* noalias %P2) { +; Note: in this test we //can// GVN %v1 and %v2 into one value in theory. Calls +; with deopt operand bundles are not argmemonly because they *read* the entire +; heap, but they don't write to any location in the heap if the callee does not +; deoptimize the caller. This fact, combined with the fact that +; @argmemonly_function is, well, an argmemonly function, can be used to conclude +; that %P is not written to at the callsite. However LLVM currently cannot +; describe the "does not write to non-args, and reads the entire heap" effect on +; a callsite. + +; CHECK-LABEL: @test2( + %v1 = load i32, i32* %P +; CHECK: %v1 = load i32, i32* %P + call void @argmemonly_function(i32* %P2) [ "deopt"() ] +; CHECK: call void @argmemonly_function( + %v2 = load i32, i32* %P +; CHECK: %v2 = load i32, i32* %P + %diff = sub i32 %v1, %v2 +; CHECK: %diff = sub i32 %v1, %v2 + ret i32 %diff +; CHECK: ret i32 %diff +} |
