[X86] Replace custom scalar integer absolute matching with ISD::ABS lowering.
x86 has its own copy of integer absolute pattern matching to combine directly to a SUB+CMOV.
This patch removes the x86 combine and adds custom lowering support for ISD::ABS instead, allowing us to use the DAGCombiner version.
Additional test cases are already covered by iabs.ll (rL315706 and rL315711).
Differential Revision: https://reviews.llvm.org/D38895
llvm-svn: 316162
diff --git a/llvm/test/CodeGen/X86/combine-abs.ll b/llvm/test/CodeGen/X86/combine-abs.ll
index fa476a2..a53a13a 100644
--- a/llvm/test/CodeGen/X86/combine-abs.ll
+++ b/llvm/test/CodeGen/X86/combine-abs.ll
@@ -26,12 +26,9 @@
define i32 @combine_i32_abs_abs(i32 %a) {
; CHECK-LABEL: combine_i32_abs_abs:
; CHECK: # BB#0:
-; CHECK-NEXT: movl %edi, %ecx
-; CHECK-NEXT: negl %ecx
-; CHECK-NEXT: cmovll %edi, %ecx
-; CHECK-NEXT: movl %ecx, %eax
+; CHECK-NEXT: movl %edi, %eax
; CHECK-NEXT: negl %eax
-; CHECK-NEXT: cmovll %ecx, %eax
+; CHECK-NEXT: cmovll %edi, %eax
; CHECK-NEXT: retq
%n1 = sub i32 zeroinitializer, %a
%b1 = icmp slt i32 %a, zeroinitializer