[DAGCombiner] Some very basic add/sub saturation combines.
Handle combines with zero and constant canonicalization for adds.
llvm-svn: 351024
diff --git a/llvm/test/CodeGen/X86/combine-sub-ssat.ll b/llvm/test/CodeGen/X86/combine-sub-ssat.ll
index 8d53300..a17573d 100644
--- a/llvm/test/CodeGen/X86/combine-sub-ssat.ll
+++ b/llvm/test/CodeGen/X86/combine-sub-ssat.ll
@@ -15,30 +15,16 @@
define i32 @combine_zero_i32(i32 %a0) {
; CHECK-LABEL: combine_zero_i32:
; CHECK: # %bb.0:
-; CHECK-NEXT: xorl %eax, %eax
-; CHECK-NEXT: movl %edi, %ecx
-; CHECK-NEXT: subl $0, %ecx
-; CHECK-NEXT: setns %al
-; CHECK-NEXT: addl $2147483647, %eax # imm = 0x7FFFFFFF
-; CHECK-NEXT: subl $0, %edi
-; CHECK-NEXT: cmovnol %edi, %eax
+; CHECK-NEXT: movl %edi, %eax
; CHECK-NEXT: retq
%1 = call i32 @llvm.ssub.sat.i32(i32 %a0, i32 0);
ret i32 %1
}
define <8 x i16> @combine_zero_v8i16(<8 x i16> %a0) {
-; SSE-LABEL: combine_zero_v8i16:
-; SSE: # %bb.0:
-; SSE-NEXT: pxor %xmm1, %xmm1
-; SSE-NEXT: psubsw %xmm1, %xmm0
-; SSE-NEXT: retq
-;
-; AVX-LABEL: combine_zero_v8i16:
-; AVX: # %bb.0:
-; AVX-NEXT: vpxor %xmm1, %xmm1, %xmm1
-; AVX-NEXT: vpsubsw %xmm1, %xmm0, %xmm0
-; AVX-NEXT: retq
+; CHECK-LABEL: combine_zero_v8i16:
+; CHECK: # %bb.0:
+; CHECK-NEXT: retq
%1 = call <8 x i16> @llvm.ssub.sat.v8i16(<8 x i16> %a0, <8 x i16> zeroinitializer);
ret <8 x i16> %1
}