diff options
Diffstat (limited to 'test/CodeGen/X86/cse-add-with-overflow.ll')
| -rw-r--r-- | test/CodeGen/X86/cse-add-with-overflow.ll | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/test/CodeGen/X86/cse-add-with-overflow.ll b/test/CodeGen/X86/cse-add-with-overflow.ll new file mode 100644 index 0000000..1fcc03f --- /dev/null +++ b/test/CodeGen/X86/cse-add-with-overflow.ll @@ -0,0 +1,43 @@ +; RUN: llc < %s -mtriple=x86_64-darwin -mcpu=generic | FileCheck %s +; XFAIL: * +; rdar:15661073 simple example of redundant adds +; +; MachineCSE should coalesce trivial subregister copies. +; +; The extra movl+addl should be removed during MachineCSE. +; CHECK-LABEL: redundantadd +; CHECK: cmpq +; CHECK: movq +; CHECK-NOT: movl +; CHECK: addl +; CHECK-NOT: addl +; CHECK: ret + +define i64 @redundantadd(i64* %a0, i64* %a1) { +entry: + %tmp8 = load i64* %a0, align 8 + %tmp12 = load i64* %a1, align 8 + %tmp13 = icmp ult i64 %tmp12, -281474976710656 + br i1 %tmp13, label %exit1, label %body + +exit1: + unreachable + +body: + %tmp14 = trunc i64 %tmp8 to i32 + %tmp15 = trunc i64 %tmp12 to i32 + %tmp16 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %tmp14, i32 %tmp15) + %tmp17 = extractvalue { i32, i1 } %tmp16, 1 + br i1 %tmp17, label %exit2, label %return + +exit2: + unreachable + +return: + %tmp18 = add i64 %tmp12, %tmp8 + %tmp19 = and i64 %tmp18, 4294967295 + %tmp20 = or i64 %tmp19, -281474976710656 + ret i64 %tmp20 +} + +declare { i32, i1 } @llvm.sadd.with.overflow.i32(i32, i32) |