[InstCombine] add tests for smin/smax intrinsics with negated ops; NFC

Author: rotateright

llvm/test/Transforms/InstCombine/minmax-intrinsics.ll

@@ -1030,3 +1030,115 @@ define i8 @umin_demand_and_7_8(i8 %x) {
   %r = and i8 %m, -8
   ret i8 %r
 }
+
+define i8 @neg_neg_nsw_smax(i8 %x, i8 %y) {
+; CHECK-LABEL: @neg_neg_nsw_smax(
+; CHECK-NEXT:    [[NX:%.*]] = sub nsw i8 0, [[X:%.*]]
+; CHECK-NEXT:    [[NY:%.*]] = sub nsw i8 0, [[Y:%.*]]
+; CHECK-NEXT:    [[M:%.*]] = call i8 @llvm.smax.i8(i8 [[NX]], i8 [[NY]])
+; CHECK-NEXT:    ret i8 [[M]]
+;
+  %nx = sub nsw i8 0, %x
+  %ny = sub nsw i8 0, %y
+  %m = call i8 @llvm.smax.i8(i8 %nx, i8 %ny)
+  ret i8 %m
+}
+
+define <3 x i8> @neg_neg_nsw_smin(<3 x i8> %x, <3 x i8> %y) {
+; CHECK-LABEL: @neg_neg_nsw_smin(
+; CHECK-NEXT:    [[NX:%.*]] = sub nsw <3 x i8> zeroinitializer, [[X:%.*]]
+; CHECK-NEXT:    [[NY:%.*]] = sub nsw <3 x i8> zeroinitializer, [[Y:%.*]]
+; CHECK-NEXT:    [[M:%.*]] = call <3 x i8> @llvm.smin.v3i8(<3 x i8> [[NX]], <3 x i8> [[NY]])
+; CHECK-NEXT:    ret <3 x i8> [[M]]
+;
+  %nx = sub nsw <3 x i8> zeroinitializer, %x
+  %ny = sub nsw <3 x i8> zeroinitializer, %y
+  %m = call <3 x i8> @llvm.smin.v3i8(<3 x i8> %nx, <3 x i8> %ny)
+  ret <3 x i8> %m
+}
+
+define i8 @neg_neg_nsw_smax_use0(i8 %x, i8 %y) {
+; CHECK-LABEL: @neg_neg_nsw_smax_use0(
+; CHECK-NEXT:    [[NX:%.*]] = sub nsw i8 0, [[X:%.*]]
+; CHECK-NEXT:    call void @use(i8 [[NX]])
+; CHECK-NEXT:    [[NY:%.*]] = sub nsw i8 0, [[Y:%.*]]
+; CHECK-NEXT:    [[M:%.*]] = call i8 @llvm.smax.i8(i8 [[NX]], i8 [[NY]])
+; CHECK-NEXT:    ret i8 [[M]]
+;
+  %nx = sub nsw i8 0, %x
+  call void @use(i8 %nx)
+  %ny = sub nsw i8 0, %y
+  %m = call i8 @llvm.smax.i8(i8 %nx, i8 %ny)
+  ret i8 %m
+}
+
+define i8 @neg_neg_nsw_smin_use1(i8 %x, i8 %y) {
+; CHECK-LABEL: @neg_neg_nsw_smin_use1(
+; CHECK-NEXT:    [[NX:%.*]] = sub nsw i8 0, [[X:%.*]]
+; CHECK-NEXT:    [[NY:%.*]] = sub nsw i8 0, [[Y:%.*]]
+; CHECK-NEXT:    call void @use(i8 [[NY]])
+; CHECK-NEXT:    [[M:%.*]] = call i8 @llvm.smin.i8(i8 [[NX]], i8 [[NY]])
+; CHECK-NEXT:    ret i8 [[M]]
+;
+  %nx = sub nsw i8 0, %x
+  %ny = sub nsw i8 0, %y
+  call void @use(i8 %ny)
+  %m = call i8 @llvm.smin.i8(i8 %nx, i8 %ny)
+  ret i8 %m
+}
+
+define i8 @neg_neg_nsw_smin_use2(i8 %x, i8 %y) {
+; CHECK-LABEL: @neg_neg_nsw_smin_use2(
+; CHECK-NEXT:    [[NX:%.*]] = sub nsw i8 0, [[X:%.*]]
+; CHECK-NEXT:    call void @use(i8 [[NX]])
+; CHECK-NEXT:    [[NY:%.*]] = sub nsw i8 0, [[Y:%.*]]
+; CHECK-NEXT:    call void @use(i8 [[NY]])
+; CHECK-NEXT:    [[M:%.*]] = call i8 @llvm.smin.i8(i8 [[NX]], i8 [[NY]])
+; CHECK-NEXT:    ret i8 [[M]]
+;
+  %nx = sub nsw i8 0, %x
+  call void @use(i8 %nx)
+  %ny = sub nsw i8 0, %y
+  call void @use(i8 %ny)
+  %m = call i8 @llvm.smin.i8(i8 %nx, i8 %ny)
+  ret i8 %m
+}
+
+define i8 @neg_neg_smax(i8 %x, i8 %y) {
+; CHECK-LABEL: @neg_neg_smax(
+; CHECK-NEXT:    [[NX:%.*]] = sub i8 0, [[X:%.*]]
+; CHECK-NEXT:    [[NY:%.*]] = sub nsw i8 0, [[Y:%.*]]
+; CHECK-NEXT:    [[M:%.*]] = call i8 @llvm.smax.i8(i8 [[NX]], i8 [[NY]])
+; CHECK-NEXT:    ret i8 [[M]]
+;
+  %nx = sub i8 0, %x
+  %ny = sub nsw i8 0, %y
+  %m = call i8 @llvm.smax.i8(i8 %nx, i8 %ny)
+  ret i8 %m
+}
+
+define i8 @neg_neg_smin(i8 %x, i8 %y) {
+; CHECK-LABEL: @neg_neg_smin(
+; CHECK-NEXT:    [[NX:%.*]] = sub i8 0, [[X:%.*]]
+; CHECK-NEXT:    [[NY:%.*]] = sub nsw i8 0, [[Y:%.*]]
+; CHECK-NEXT:    [[M:%.*]] = call i8 @llvm.smin.i8(i8 [[NX]], i8 [[NY]])
+; CHECK-NEXT:    ret i8 [[M]]
+;
+  %nx = sub i8 0, %x
+  %ny = sub nsw i8 0, %y
+  %m = call i8 @llvm.smin.i8(i8 %nx, i8 %ny)
+  ret i8 %m
+}
+
+define i8 @neg_neg_nsw_umin(i8 %x, i8 %y) {
+; CHECK-LABEL: @neg_neg_nsw_umin(
+; CHECK-NEXT:    [[NX:%.*]] = sub nsw i8 0, [[X:%.*]]
+; CHECK-NEXT:    [[NY:%.*]] = sub nsw i8 0, [[Y:%.*]]
+; CHECK-NEXT:    [[M:%.*]] = call i8 @llvm.umin.i8(i8 [[NX]], i8 [[NY]])
+; CHECK-NEXT:    ret i8 [[M]]
+;
+  %nx = sub nsw i8 0, %x
+  %ny = sub nsw i8 0, %y
+  %m = call i8 @llvm.umin.i8(i8 %nx, i8 %ny)
+  ret i8 %m
+}