[InstCombine] Add tests for binop of shift fold (NFC)

diff --git a/llvm/test/Transforms/InstCombine/binop-of-displaced-shifts.ll b/llvm/test/Transforms/InstCombine/binop-of-displaced-shifts.ll
new file mode 100644 (file)
index 0000000..3a5384b
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/binop-of-displaced-shifts.ll
@@ -0,0 +1,314 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 2
+; RUN: opt -S -passes=instcombine < %s | FileCheck %s
+
+define i8 @shl_or(i8 %x) {
+; CHECK-LABEL: define i8 @shl_or
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl i8 16, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = shl i8 3, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = or i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = shl i8 16, %x
+  %add = add i8 %x, 1
+  %shift2 = shl i8 3, %add
+  %binop = or i8 %shift, %shift2
+  ret i8 %binop
+}
+
+define i8 @lshr_or(i8 %x) {
+; CHECK-LABEL: define i8 @lshr_or
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = lshr i8 16, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = lshr i8 3, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = or i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = lshr i8 16, %x
+  %add = add i8 %x, 1
+  %shift2 = lshr i8 3, %add
+  %binop = or i8 %shift, %shift2
+  ret i8 %binop
+}
+
+define i8 @ashr_or(i8 %x) {
+; CHECK-LABEL: define i8 @ashr_or
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = ashr i8 -64, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = ashr i8 -128, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = or i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = ashr i8 -64, %x
+  %add = add i8 %x, 1
+  %shift2 = ashr i8 -128, %add
+  %binop = or i8 %shift, %shift2
+  ret i8 %binop
+}
+
+define i8 @shl_xor(i8 %x) {
+; CHECK-LABEL: define i8 @shl_xor
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl i8 16, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = shl i8 3, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = xor i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = shl i8 16, %x
+  %add = add i8 %x, 1
+  %shift2 = shl i8 3, %add
+  %binop = xor i8 %shift, %shift2
+  ret i8 %binop
+}
+
+define i8 @lshr_xor(i8 %x) {
+; CHECK-LABEL: define i8 @lshr_xor
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = lshr i8 16, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = lshr i8 3, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = xor i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = lshr i8 16, %x
+  %add = add i8 %x, 1
+  %shift2 = lshr i8 3, %add
+  %binop = xor i8 %shift, %shift2
+  ret i8 %binop
+}
+
+define i8 @ashr_xor(i8 %x) {
+; CHECK-LABEL: define i8 @ashr_xor
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = ashr i8 -128, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = ashr i8 -64, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = xor i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = ashr i8 -128, %x
+  %add = add i8 %x, 1
+  %shift2 = ashr i8 -64, %add
+  %binop = xor i8 %shift, %shift2
+  ret i8 %binop
+}
+
+define i8 @shl_and(i8 %x) {
+; CHECK-LABEL: define i8 @shl_and
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl i8 48, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = shl i8 8, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = and i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = shl i8 48, %x
+  %add = add i8 %x, 1
+  %shift2 = shl i8 8, %add
+  %binop = and i8 %shift, %shift2
+  ret i8 %binop
+}
+
+define i8 @lshr_and(i8 %x) {
+; CHECK-LABEL: define i8 @lshr_and
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = lshr i8 48, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = lshr i8 64, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = and i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = lshr i8 48, %x
+  %add = add i8 %x, 1
+  %shift2 = lshr i8 64, %add
+  %binop = and i8 %shift, %shift2
+  ret i8 %binop
+}
+
+define i8 @ashr_and(i8 %x) {
+; CHECK-LABEL: define i8 @ashr_and
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = ashr i8 -64, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = ashr i8 -128, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = and i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = ashr i8 -64, %x
+  %add = add i8 %x, 1
+  %shift2 = ashr i8 -128, %add
+  %binop = and i8 %shift, %shift2
+  ret i8 %binop
+}
+
+define i8 @shl_or_commuted(i8 %x) {
+; CHECK-LABEL: define i8 @shl_or_commuted
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl i8 16, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = shl i8 3, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = or i8 [[SHIFT2]], [[SHIFT]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = shl i8 16, %x
+  %add = add i8 %x, 1
+  %shift2 = shl i8 3, %add
+  %binop = or i8 %shift2, %shift
+  ret i8 %binop
+}
+
+define <2 x i8> @shl_or_splat(<2 x i8> %x) {
+; CHECK-LABEL: define <2 x i8> @shl_or_splat
+; CHECK-SAME: (<2 x i8> [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl <2 x i8> <i8 16, i8 16>, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add <2 x i8> [[X]], <i8 1, i8 1>
+; CHECK-NEXT:    [[SHIFT2:%.*]] = shl <2 x i8> <i8 3, i8 3>, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = or <2 x i8> [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret <2 x i8> [[BINOP]]
+;
+  %shift = shl <2 x i8> <i8 16, i8 16>, %x
+  %add = add <2 x i8> %x, <i8 1, i8 1>
+  %shift2 = shl <2 x i8> <i8 3, i8 3>, %add
+  %binop = or <2 x i8> %shift, %shift2
+  ret <2 x i8> %binop
+}
+
+define <2 x i8> @shl_or_non_splat(<2 x i8> %x) {
+; CHECK-LABEL: define <2 x i8> @shl_or_non_splat
+; CHECK-SAME: (<2 x i8> [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl <2 x i8> <i8 16, i8 32>, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add <2 x i8> [[X]], <i8 1, i8 2>
+; CHECK-NEXT:    [[SHIFT2:%.*]] = shl <2 x i8> <i8 3, i8 7>, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = or <2 x i8> [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret <2 x i8> [[BINOP]]
+;
+  %shift = shl <2 x i8> <i8 16, i8 32>, %x
+  %add = add <2 x i8> %x, <i8 1, i8 2>
+  %shift2 = shl <2 x i8> <i8 3, i8 7>, %add
+  %binop = or <2 x i8> %shift, %shift2
+  ret <2 x i8> %binop
+}
+
+define <2 x i8> @shl_or_undef_in_add(<2 x i8> %x) {
+; CHECK-LABEL: define <2 x i8> @shl_or_undef_in_add
+; CHECK-SAME: (<2 x i8> [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl <2 x i8> <i8 16, i8 16>, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add <2 x i8> [[X]], <i8 1, i8 undef>
+; CHECK-NEXT:    [[SHIFT2:%.*]] = shl <2 x i8> <i8 3, i8 3>, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = or <2 x i8> [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret <2 x i8> [[BINOP]]
+;
+  %shift = shl <2 x i8> <i8 16, i8 16>, %x
+  %add = add <2 x i8> %x, <i8 1, i8 undef>
+  %shift2 = shl <2 x i8> <i8 3, i8 3>, %add
+  %binop = or <2 x i8> %shift, %shift2
+  ret <2 x i8> %binop
+}
+
+define <2 x i8> @shl_or_undef_in_shift1(<2 x i8> %x) {
+; CHECK-LABEL: define <2 x i8> @shl_or_undef_in_shift1
+; CHECK-SAME: (<2 x i8> [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl <2 x i8> <i8 16, i8 undef>, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add <2 x i8> [[X]], <i8 1, i8 1>
+; CHECK-NEXT:    [[SHIFT2:%.*]] = shl <2 x i8> <i8 3, i8 3>, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = or <2 x i8> [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret <2 x i8> [[BINOP]]
+;
+  %shift = shl <2 x i8> <i8 16, i8 undef>, %x
+  %add = add <2 x i8> %x, <i8 1, i8 1>
+  %shift2 = shl <2 x i8> <i8 3, i8 3>, %add
+  %binop = or <2 x i8> %shift, %shift2
+  ret <2 x i8> %binop
+}
+
+define <2 x i8> @shl_or_undef_in_shift2(<2 x i8> %x) {
+; CHECK-LABEL: define <2 x i8> @shl_or_undef_in_shift2
+; CHECK-SAME: (<2 x i8> [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl <2 x i8> <i8 16, i8 16>, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add <2 x i8> [[X]], <i8 1, i8 1>
+; CHECK-NEXT:    [[SHIFT2:%.*]] = shl <2 x i8> <i8 3, i8 undef>, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = or <2 x i8> [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret <2 x i8> [[BINOP]]
+;
+  %shift = shl <2 x i8> <i8 16, i8 16>, %x
+  %add = add <2 x i8> %x, <i8 1, i8 1>
+  %shift2 = shl <2 x i8> <i8 3, i8 undef>, %add
+  %binop = or <2 x i8> %shift, %shift2
+  ret <2 x i8> %binop
+}
+
+declare void @use(i8)
+
+define i8 @shl_or_multiuse(i8 %x) {
+; CHECK-LABEL: define i8 @shl_or_multiuse
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl i8 16, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = shl i8 3, [[ADD]]
+; CHECK-NEXT:    call void @use(i8 [[SHIFT]])
+; CHECK-NEXT:    call void @use(i8 [[ADD]])
+; CHECK-NEXT:    call void @use(i8 [[SHIFT2]])
+; CHECK-NEXT:    [[BINOP:%.*]] = or i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = shl i8 16, %x
+  %add = add i8 %x, 1
+  %shift2 = shl i8 3, %add
+  call void @use(i8 %shift)
+  call void @use(i8 %add)
+  call void @use(i8 %shift2)
+  %binop = or i8 %shift, %shift2
+  ret i8 %binop
+}
+
+define i8 @mismatched_shifts(i8 %x) {
+; CHECK-LABEL: define i8 @mismatched_shifts
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl i8 16, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = lshr i8 3, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = or i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = shl i8 16, %x
+  %add = add i8 %x, 1
+  %shift2 = lshr i8 3, %add
+  %binop = or i8 %shift, %shift2
+  ret i8 %binop
+}
+
+define i8 @mismatched_ops(i8 %x, i8 %y) {
+; CHECK-LABEL: define i8 @mismatched_ops
+; CHECK-SAME: (i8 [[X:%.*]], i8 [[Y:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl i8 16, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[Y]], 1
+; CHECK-NEXT:    [[SHIFT2:%.*]] = shl i8 3, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = or i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = shl i8 16, %x
+  %add = add i8 %y, 1
+  %shift2 = shl i8 3, %add
+  %binop = or i8 %shift, %shift2
+  ret i8 %binop
+}
+
+define i8 @add_out_of_range(i8 %x) {
+; CHECK-LABEL: define i8 @add_out_of_range
+; CHECK-SAME: (i8 [[X:%.*]]) {
+; CHECK-NEXT:    [[SHIFT:%.*]] = shl i8 16, [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], 32
+; CHECK-NEXT:    [[SHIFT2:%.*]] = shl i8 3, [[ADD]]
+; CHECK-NEXT:    [[BINOP:%.*]] = or i8 [[SHIFT]], [[SHIFT2]]
+; CHECK-NEXT:    ret i8 [[BINOP]]
+;
+  %shift = shl i8 16, %x
+  %add = add i8 %x, 32
+  %shift2 = shl i8 3, %add
+  %binop = or i8 %shift, %shift2
+  ret i8 %binop
+}