[llvm] r286737 - [x86] add smin/smax with zero tests

[Sanjay Patel via llvm-commits]

Author: spatel
Date: Sat Nov 12 18:32:39 2016
New Revision: 286737

URL: http://llvm.org/viewvc/llvm-project?rev=286737&view=rev
Log:
[x86] add smin/smax with zero tests

These are vector tests corresponding to the discussion at:
http://lists.llvm.org/pipermail/llvm-dev/2016-November/106868.html

Apart from the lack of min/max matching, the and/andn difference 
shows a lack of DAG-level canonicalization.


Modified:
    llvm/trunk/test/CodeGen/X86/vec_minmax_match.ll

Modified: llvm/trunk/test/CodeGen/X86/vec_minmax_match.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/vec_minmax_match.ll?rev=286737&r1=286736&r2=286737&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/vec_minmax_match.ll (original)
+++ llvm/trunk/test/CodeGen/X86/vec_minmax_match.ll Sat Nov 12 18:32:39 2016
@@ -32,6 +32,38 @@ define <4 x i32> @smin_vec2(<4 x i32> %x
   ret <4 x i32> %sel
 }
 
+; Z = X -nsw Y
+; (X >s Y) ? 0 : Z ==> (Z >s 0) ? 0 : Z ==> SMIN(Z, 0)
+define <4 x i32> @smin_vec3(<4 x i32> %x, <4 x i32> %y) {
+; CHECK-LABEL: smin_vec3:
+; CHECK:       # BB#0:
+; CHECK-NEXT:    vpsubd %xmm1, %xmm0, %xmm2
+; CHECK-NEXT:    vpcmpgtd %xmm1, %xmm0, %xmm0
+; CHECK-NEXT:    vpandn %xmm2, %xmm0, %xmm0
+; CHECK-NEXT:    retq
+;
+  %sub = sub nsw <4 x i32> %x, %y
+  %cmp = icmp sgt <4 x i32> %x, %y
+  %sel = select <4 x i1> %cmp, <4 x i32> zeroinitializer, <4 x i32> %sub
+  ret <4 x i32> %sel
+}
+
+; Z = X -nsw Y
+; (X <s Y) ? Z : 0 ==> (Z <s 0) ? Z : 0 ==> SMIN(Z, 0)
+define <4 x i32> @smin_vec4(<4 x i32> %x, <4 x i32> %y) {
+; CHECK-LABEL: smin_vec4:
+; CHECK:       # BB#0:
+; CHECK-NEXT:    vpsubd %xmm1, %xmm0, %xmm2
+; CHECK-NEXT:    vpcmpgtd %xmm0, %xmm1, %xmm0
+; CHECK-NEXT:    vpand %xmm2, %xmm0, %xmm0
+; CHECK-NEXT:    retq
+;
+  %sub = sub nsw <4 x i32> %x, %y
+  %cmp = icmp slt <4 x i32> %x, %y
+  %sel = select <4 x i1> %cmp, <4 x i32> %sub, <4 x i32> zeroinitializer
+  ret <4 x i32> %sel
+}
+
 define <4 x i32> @smax_vec1(<4 x i32> %x) {
 ; CHECK-LABEL: smax_vec1:
 ; CHECK:       # BB#0:
@@ -60,6 +92,38 @@ define <4 x i32> @smax_vec2(<4 x i32> %x
   ret <4 x i32> %sel
 }
 
+; Z = X -nsw Y
+; (X <s Y) ? 0 : Z ==> (Z <s 0) ? 0 : Z ==> SMAX(Z, 0)
+define <4 x i32> @smax_vec3(<4 x i32> %x, <4 x i32> %y) {
+; CHECK-LABEL: smax_vec3:
+; CHECK:       # BB#0:
+; CHECK-NEXT:    vpsubd %xmm1, %xmm0, %xmm2
+; CHECK-NEXT:    vpcmpgtd %xmm0, %xmm1, %xmm0
+; CHECK-NEXT:    vpandn %xmm2, %xmm0, %xmm0
+; CHECK-NEXT:    retq
+;
+  %sub = sub nsw <4 x i32> %x, %y
+  %cmp = icmp slt <4 x i32> %x, %y
+  %sel = select <4 x i1> %cmp, <4 x i32> zeroinitializer, <4 x i32> %sub
+  ret <4 x i32> %sel
+}
+
+; Z = X -nsw Y
+; (X >s Y) ? Z : 0 ==> (Z >s 0) ? Z : 0 ==> SMAX(Z, 0)
+define <4 x i32> @smax_vec4(<4 x i32> %x, <4 x i32> %y) {
+; CHECK-LABEL: smax_vec4:
+; CHECK:       # BB#0:
+; CHECK-NEXT:    vpsubd %xmm1, %xmm0, %xmm2
+; CHECK-NEXT:    vpcmpgtd %xmm1, %xmm0, %xmm0
+; CHECK-NEXT:    vpand %xmm2, %xmm0, %xmm0
+; CHECK-NEXT:    retq
+;
+  %sub = sub nsw <4 x i32> %x, %y
+  %cmp = icmp sgt <4 x i32> %x, %y
+  %sel = select <4 x i1> %cmp, <4 x i32> %sub, <4 x i32> zeroinitializer
+  ret <4 x i32> %sel
+}
+
 define <4 x i32> @umax_vec1(<4 x i32> %x) {
 ; CHECK-LABEL: umax_vec1:
 ; CHECK:       # BB#0: