[InstCombine] Add an extra test for udiv_shl_pair_const with vscale

Author: davemgreen

llvm/test/Transforms/InstCombine/AArch64/sve-intrinsic-opts-counting-elems.ll

@@ -240,6 +240,23 @@ define i64 @cntd_all() {
 }
 
 
+define i64 @udiv() vscale_range(1, 16) {
+; CHECK-LABEL: @udiv(
+; CHECK-NEXT:    [[TMP2:%.*]] = call i64 @llvm.vscale.i64()
+; CHECK-NEXT:    [[B:%.*]] = shl nuw nsw i64 [[TMP2]], 4
+; CHECK-NEXT:    [[TMP3:%.*]] = call i64 @llvm.vscale.i64()
+; CHECK-NEXT:    [[B1:%.*]] = shl nuw nsw i64 [[TMP3]], 2
+; CHECK-NEXT:    [[TMP4:%.*]] = call range(i64 2, 65) i64 @llvm.cttz.i64(i64 [[B1]], i1 true)
+; CHECK-NEXT:    [[C:%.*]] = lshr i64 [[B]], [[TMP4]]
+; CHECK-NEXT:    ret i64 [[C]]
+;
+  %a = call i64 @llvm.aarch64.sve.cntb(i32 31)
+  %b = call i64 @llvm.aarch64.sve.cntw(i32 31)
+  %c = udiv i64 %a, %b
+  ret i64 %c
+}
+
+
 declare i64 @llvm.aarch64.sve.cntb(i32 %pattern)
 declare i64 @llvm.aarch64.sve.cnth(i32 %pattern)
 declare i64 @llvm.aarch64.sve.cntw(i32 %pattern)

llvm/test/Transforms/InstCombine/div-shift.ll

@@ -1399,3 +1399,23 @@ start:
   %div = udiv i8 %x, %y
   ret i8 %div
 }
+
+define i32 @udiv_shl_pair_const_vscale() vscale_range(1, 16) {
+; CHECK-LABEL: @udiv_shl_pair_const_vscale(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[A:%.*]] = call i32 @llvm.vscale.i32()
+; CHECK-NEXT:    [[B:%.*]] = call i32 @llvm.vscale.i32()
+; CHECK-NEXT:    [[LHS:%.*]] = shl nuw nsw i32 [[A]], 2
+; CHECK-NEXT:    [[RHS:%.*]] = shl nuw nsw i32 [[B]], 1
+; CHECK-NEXT:    [[TMP0:%.*]] = call range(i32 1, 33) i32 @llvm.cttz.i32(i32 [[RHS]], i1 true)
+; CHECK-NEXT:    [[DIV:%.*]] = lshr i32 [[LHS]], [[TMP0]]
+; CHECK-NEXT:    ret i32 [[DIV]]
+;
+entry:
+  %a = call i32 @llvm.vscale()
+  %b = call i32 @llvm.vscale()
+  %lhs = shl nuw i32 %a, 2
+  %rhs = shl nuw i32 %b, 1
+  %div = udiv i32 %lhs, %rhs
+  ret i32 %div
+}