From 31291a403c8a759aa4a33db7502730929db416a3 Mon Sep 17 00:00:00 2001
From: Amaury Sechet <deadalnix@gmail.com>
Date: Sat, 2 Mar 2019 14:28:59 +0000
Subject: [PATCH] Add test case for add to sub transformation. NFC

llvm-svn: 355269
---
 llvm/test/CodeGen/X86/add.ll | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/llvm/test/CodeGen/X86/add.ll b/llvm/test/CodeGen/X86/add.ll
index a8c254f4b0fe..c54711a93a73 100644
--- a/llvm/test/CodeGen/X86/add.ll
+++ b/llvm/test/CodeGen/X86/add.ll
@@ -477,3 +477,33 @@ define void @uaddo1_not(i32 %a, i32* %p0, i1* %p1) {
   store i1 %r1, i1* %p1
   ret void
 }
+
+define i32 @add_to_sub(i32 %a, i32 %b) {
+; X32-LABEL: add_to_sub:
+; X32:       # %bb.0:
+; X32-NEXT:    movl {{[0-9]+}}(%esp), %eax
+; X32-NEXT:    movl {{[0-9]+}}(%esp), %ecx
+; X32-NEXT:    notl %ecx
+; X32-NEXT:    leal 1(%ecx,%eax), %eax
+; X32-NEXT:    retl
+;
+; X64-LINUX-LABEL: add_to_sub:
+; X64-LINUX:       # %bb.0:
+; X64-LINUX-NEXT:    # kill: def $esi killed $esi def $rsi
+; X64-LINUX-NEXT:    # kill: def $edi killed $edi def $rdi
+; X64-LINUX-NEXT:    notl %edi
+; X64-LINUX-NEXT:    leal 1(%rdi,%rsi), %eax
+; X64-LINUX-NEXT:    retq
+;
+; X64-WIN32-LABEL: add_to_sub:
+; X64-WIN32:       # %bb.0:
+; X64-WIN32-NEXT:    # kill: def $edx killed $edx def $rdx
+; X64-WIN32-NEXT:    # kill: def $ecx killed $ecx def $rcx
+; X64-WIN32-NEXT:    notl %ecx
+; X64-WIN32-NEXT:    leal 1(%rcx,%rdx), %eax
+; X64-WIN32-NEXT:    retq
+  %nota = xor i32 %a, -1
+  %add = add i32 %nota, %b
+  %r = add i32 %add, 1
+  ret i32 %r
+}