From 5fe70be7998da1d67b463af87bc0af524a0953c6 Mon Sep 17 00:00:00 2001
From: Noah Goldstein <goldstein.w.n@gmail.com>
Date: Sun, 29 Jan 2023 16:02:32 -0600
Subject: [PATCH] Add tests for KnownBits of (and/xor/or X, (add/sub X, OddV));
 NFC

Differential Revision: https://reviews.llvm.org/D142426
---
 .../ValueTracking/knownbits-and-or-xor-lowbit.ll   | 281 +++++++++++++++++++++
 1 file changed, 281 insertions(+)
 create mode 100644 llvm/test/Analysis/ValueTracking/knownbits-and-or-xor-lowbit.ll

diff --git a/llvm/test/Analysis/ValueTracking/knownbits-and-or-xor-lowbit.ll b/llvm/test/Analysis/ValueTracking/knownbits-and-or-xor-lowbit.ll
new file mode 100644
index 0000000..6573ffe
--- /dev/null
+++ b/llvm/test/Analysis/ValueTracking/knownbits-and-or-xor-lowbit.ll
@@ -0,0 +1,281 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -passes=instcombine -S | FileCheck %s
+
+define <2 x i1> @sub_XY_and_bit0_is_zero(<2 x i8> %x, <2 x i8> %C) nounwind {
+; CHECK-LABEL: @sub_XY_and_bit0_is_zero(
+; CHECK-NEXT:    [[C1:%.*]] = or <2 x i8> [[C:%.*]], <i8 9, i8 9>
+; CHECK-NEXT:    [[Y:%.*]] = sub <2 x i8> [[X:%.*]], [[C1]]
+; CHECK-NEXT:    [[W:%.*]] = and <2 x i8> [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq <2 x i8> [[W]], <i8 -1, i8 -1>
+; CHECK-NEXT:    ret <2 x i1> [[R]]
+;
+  %C1 = or <2 x i8> %C, <i8 9, i8 9>
+  %y = sub <2 x i8> %x, %C1
+  %w = and <2 x i8> %x, %y
+  %r = icmp eq <2 x i8> %w, <i8 -1, i8 -1>
+  ret <2 x i1> %r
+}
+
+define i1 @sub_XY_xor_bit0_is_one(i8 %x, i8 %C) nounwind {
+; CHECK-LABEL: @sub_XY_xor_bit0_is_one(
+; CHECK-NEXT:    [[C1:%.*]] = or i8 [[C:%.*]], 1
+; CHECK-NEXT:    [[Y:%.*]] = sub i8 [[X:%.*]], [[C1]]
+; CHECK-NEXT:    [[W:%.*]] = xor i8 [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[W]], 10
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %C1 = or i8 %C, 1
+  %y = sub i8 %x, %C1
+  %w = xor i8 %x, %y
+  %r = icmp eq i8 %w, 10
+  ret i1 %r
+}
+
+define i1 @sub_XY_or_bit0_is_one(i8 %x, i8 %C) nounwind {
+; CHECK-LABEL: @sub_XY_or_bit0_is_one(
+; CHECK-NEXT:    [[C1:%.*]] = or i8 [[C:%.*]], 1
+; CHECK-NEXT:    [[Y:%.*]] = sub i8 [[X:%.*]], [[C1]]
+; CHECK-NEXT:    [[W:%.*]] = or i8 [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[W]], 10
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %C1 = or i8 %C, 1
+  %y = sub i8 %x, %C1
+  %w = or i8 %x, %y
+  %r = icmp eq i8 %w, 10
+  ret i1 %r
+}
+
+define i1 @sub_YX_and_bit0_is_zero(i8 %x, i8 %C) nounwind {
+; CHECK-LABEL: @sub_YX_and_bit0_is_zero(
+; CHECK-NEXT:    [[C1:%.*]] = or i8 [[C:%.*]], 1
+; CHECK-NEXT:    [[Y:%.*]] = sub i8 [[C1]], [[X:%.*]]
+; CHECK-NEXT:    [[W:%.*]] = and i8 [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[W]], -1
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %C1 = or i8 %C, 1
+  %y = sub i8 %C1, %x
+  %w = and i8 %x, %y
+  %r = icmp eq i8 %w, -1
+  ret i1 %r
+}
+
+define <2 x i1> @sub_YX_xor_bit0_is_one(<2 x i8> %x, <2 x i8> %C) nounwind {
+; CHECK-LABEL: @sub_YX_xor_bit0_is_one(
+; CHECK-NEXT:    [[C1:%.*]] = or <2 x i8> [[C:%.*]], <i8 1, i8 1>
+; CHECK-NEXT:    [[Y:%.*]] = sub <2 x i8> [[C1]], [[X:%.*]]
+; CHECK-NEXT:    [[W:%.*]] = xor <2 x i8> [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq <2 x i8> [[W]], <i8 12, i8 12>
+; CHECK-NEXT:    ret <2 x i1> [[R]]
+;
+  %C1 = or <2 x i8> %C, <i8 1, i8 1>
+  %y = sub <2 x i8> %C1, %x
+  %w = xor <2 x i8> %x, %y
+  %r = icmp eq <2 x i8> %w, <i8 12, i8 12>
+  ret <2 x i1> %r
+}
+
+define i1 @sub_YX_or_bit0_is_one(i8 %x, i8 %C) nounwind {
+; CHECK-LABEL: @sub_YX_or_bit0_is_one(
+; CHECK-NEXT:    [[C1:%.*]] = or i8 [[C:%.*]], 1
+; CHECK-NEXT:    [[Y:%.*]] = sub i8 [[C1]], [[X:%.*]]
+; CHECK-NEXT:    [[W:%.*]] = or i8 [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[W]], 32
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %C1 = or i8 %C, 1
+  %y = sub i8 %C1, %x
+  %w = or i8 %x, %y
+  %r = icmp eq i8 %w, 32
+  ret i1 %r
+}
+
+define i1 @add_YX_xor_bit0_is_one(i8 %x, i8 %C) nounwind {
+; CHECK-LABEL: @add_YX_xor_bit0_is_one(
+; CHECK-NEXT:    [[C1:%.*]] = or i8 [[C:%.*]], 1
+; CHECK-NEXT:    [[Y:%.*]] = add i8 [[C1]], [[X:%.*]]
+; CHECK-NEXT:    [[W:%.*]] = xor i8 [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[W]], 32
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %C1 = or i8 %C, 1
+  %y = add i8 %C1, %x
+  %w = xor i8 %x, %y
+  %r = icmp eq i8 %w, 32
+  ret i1 %r
+}
+
+define <2 x i1> @add_XY_or_bit0_is_one(<2 x i8> %x, <2 x i8> %C) nounwind {
+; CHECK-LABEL: @add_XY_or_bit0_is_one(
+; CHECK-NEXT:    [[C1:%.*]] = or <2 x i8> [[C:%.*]], <i8 1, i8 1>
+; CHECK-NEXT:    [[Y:%.*]] = add <2 x i8> [[C1]], [[X:%.*]]
+; CHECK-NEXT:    [[W:%.*]] = or <2 x i8> [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq <2 x i8> [[W]], <i8 90, i8 90>
+; CHECK-NEXT:    ret <2 x i1> [[R]]
+;
+  %C1 = or <2 x i8> %C, <i8 1, i8 1>
+  %y = add <2 x i8> %C1, %x
+  %w = or <2 x i8> %x, %y
+  %r = icmp eq <2 x i8> %w, <i8 90, i8 90>
+  ret <2 x i1> %r
+}
+
+define <2 x i1> @sub_XY_and_bit0_is_zero_fail(<2 x i8> %x, <2 x i8> %C) nounwind {
+; CHECK-LABEL: @sub_XY_and_bit0_is_zero_fail(
+; CHECK-NEXT:    [[C1:%.*]] = or <2 x i8> [[C:%.*]], <i8 8, i8 8>
+; CHECK-NEXT:    [[Y:%.*]] = sub <2 x i8> [[X:%.*]], [[C1]]
+; CHECK-NEXT:    [[W:%.*]] = and <2 x i8> [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq <2 x i8> [[W]], <i8 -1, i8 -1>
+; CHECK-NEXT:    ret <2 x i1> [[R]]
+;
+  %C1 = or <2 x i8> %C, <i8 8, i8 8>
+  %y = sub <2 x i8> %x, %C1
+  %w = and <2 x i8> %x, %y
+  %r = icmp eq <2 x i8> %w, <i8 -1, i8 -1>
+  ret <2 x i1> %r
+}
+
+define i1 @sub_XY_xor_bit0_is_one_fail(i8 %x, i8 %C) nounwind {
+; CHECK-LABEL: @sub_XY_xor_bit0_is_one_fail(
+; CHECK-NEXT:    [[TMP1:%.*]] = xor i8 [[C:%.*]], -2
+; CHECK-NEXT:    [[C1_NEG:%.*]] = add i8 [[TMP1]], 1
+; CHECK-NEXT:    [[Y:%.*]] = add i8 [[C1_NEG]], [[X:%.*]]
+; CHECK-NEXT:    [[W:%.*]] = xor i8 [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[W]], 10
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %C1 = xor i8 %C, 1
+  %y = sub i8 %x, %C1
+  %w = xor i8 %x, %y
+  %r = icmp eq i8 %w, 10
+  ret i1 %r
+}
+
+define i1 @sub_XY_or_bit0_is_one_fail(i8 %x, i8 %C) nounwind {
+; CHECK-LABEL: @sub_XY_or_bit0_is_one_fail(
+; CHECK-NEXT:    [[Y:%.*]] = sub i8 [[X:%.*]], [[C:%.*]]
+; CHECK-NEXT:    [[W:%.*]] = or i8 [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[W]], 10
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %y = sub i8 %x, %C
+  %w = or i8 %x, %y
+  %r = icmp eq i8 %w, 10
+  ret i1 %r
+}
+
+define i1 @sub_YX_and_bit0_is_zero_fail(i8 %x, i8 %C) nounwind {
+; CHECK-LABEL: @sub_YX_and_bit0_is_zero_fail(
+; CHECK-NEXT:    [[Y:%.*]] = sub i8 [[C:%.*]], [[X:%.*]]
+; CHECK-NEXT:    [[W:%.*]] = and i8 [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[W]], -1
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %y = sub i8 %C, %x
+  %w = and i8 %x, %y
+  %r = icmp eq i8 %w, -1
+  ret i1 %r
+}
+
+define <2 x i1> @sub_YX_xor_bit0_is_one_fail(<2 x i8> %x, <2 x i8> %C) nounwind {
+; CHECK-LABEL: @sub_YX_xor_bit0_is_one_fail(
+; CHECK-NEXT:    [[TMP1:%.*]] = xor <2 x i8> [[X:%.*]], <i8 -1, i8 -1>
+; CHECK-NEXT:    [[Y:%.*]] = add <2 x i8> [[TMP1]], [[C:%.*]]
+; CHECK-NEXT:    [[W:%.*]] = xor <2 x i8> [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq <2 x i8> [[W]], <i8 12, i8 12>
+; CHECK-NEXT:    ret <2 x i1> [[R]]
+;
+  %C1 = sub <2 x i8> %C, <i8 1, i8 1>
+  %y = sub <2 x i8> %C1, %x
+  %w = xor <2 x i8> %x, %y
+  %r = icmp eq <2 x i8> %w, <i8 12, i8 12>
+  ret <2 x i1> %r
+}
+
+define i1 @sub_YX_or_bit0_is_one_fail(i8 %x, i8 %C) nounwind {
+; CHECK-LABEL: @sub_YX_or_bit0_is_one_fail(
+; CHECK-NEXT:    [[C1:%.*]] = xor i8 [[C:%.*]], 1
+; CHECK-NEXT:    [[Y:%.*]] = sub i8 [[C1]], [[X:%.*]]
+; CHECK-NEXT:    [[W:%.*]] = or i8 [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[W]], 32
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %C1 = xor i8 %C, 1
+  %y = sub i8 %C1, %x
+  %w = or i8 %x, %y
+  %r = icmp eq i8 %w, 32
+  ret i1 %r
+}
+
+define i1 @add_YX_xor_bit0_is_one_fail(i8 %x, i8 %C) nounwind {
+; CHECK-LABEL: @add_YX_xor_bit0_is_one_fail(
+; CHECK-NEXT:    [[C1:%.*]] = and i8 [[C:%.*]], 1
+; CHECK-NEXT:    [[Y:%.*]] = add i8 [[C1]], [[X:%.*]]
+; CHECK-NEXT:    [[W:%.*]] = xor i8 [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[W]], 32
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %C1 = and i8 %C, 1
+  %y = add i8 %C1, %x
+  %w = xor i8 %x, %y
+  %r = icmp eq i8 %w, 32
+  ret i1 %r
+}
+
+define <2 x i1> @add_XY_or_bit0_is_one_fail(<2 x i8> %x, <2 x i8> %C) nounwind {
+; CHECK-LABEL: @add_XY_or_bit0_is_one_fail(
+; CHECK-NEXT:    [[C1:%.*]] = add <2 x i8> [[C:%.*]], <i8 1, i8 1>
+; CHECK-NEXT:    [[Y:%.*]] = add <2 x i8> [[C1]], [[X:%.*]]
+; CHECK-NEXT:    [[W:%.*]] = or <2 x i8> [[Y]], [[X]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq <2 x i8> [[W]], <i8 90, i8 90>
+; CHECK-NEXT:    ret <2 x i1> [[R]]
+;
+  %C1 = add <2 x i8> %C, <i8 1, i8 1>
+  %y = add <2 x i8> %C1, %x
+  %w = or <2 x i8> %x, %y
+  %r = icmp eq <2 x i8> %w, <i8 90, i8 90>
+  ret <2 x i1> %r
+}
+
+;; These tests are just to check if it can simplify using demanded bits path.
+define <2 x i32> @add_and_eval_vec(<2 x i32> %x, <2 x i32> %C) {
+; CHECK-LABEL: @add_and_eval_vec(
+; CHECK-NEXT:    [[Y:%.*]] = add <2 x i32> [[X:%.*]], <i32 1, i32 1>
+; CHECK-NEXT:    [[Z:%.*]] = and <2 x i32> [[Y]], [[X]]
+; CHECK-NEXT:    [[B:%.*]] = shl <2 x i32> [[Z]], <i32 31, i32 31>
+; CHECK-NEXT:    ret <2 x i32> [[B]]
+;
+  %y = add <2 x i32> %x, <i32 1, i32 1>
+  %z = and <2 x i32> %x, %y
+  ;; shl so we don't commute the and
+  %b = shl <2 x i32> %z, <i32 31, i32 31>
+  ret <2 x i32> %b
+}
+
+
+define <2 x i32> @add_xor_eval_vec(<2 x i32> %x) {
+; CHECK-LABEL: @add_xor_eval_vec(
+; CHECK-NEXT:    [[Y:%.*]] = add <2 x i32> [[X:%.*]], <i32 1, i32 1>
+; CHECK-NEXT:    [[Z:%.*]] = xor <2 x i32> [[Y]], [[X]]
+; CHECK-NEXT:    [[B:%.*]] = and <2 x i32> [[Z]], <i32 1, i32 1>
+; CHECK-NEXT:    ret <2 x i32> [[B]]
+;
+  %y = add <2 x i32> %x, <i32 1, i32 1>
+  %z = xor <2 x i32> %y, %x
+  %b = and <2 x i32> %z, <i32 1, i32 1>
+  ret <2 x i32> %b
+}
+
+define <2 x i32> @add_or_eval_vec(<2 x i32> %x, <2 x i32> %C) {
+; CHECK-LABEL: @add_or_eval_vec(
+; CHECK-NEXT:    [[Y:%.*]] = add <2 x i32> [[X:%.*]], <i32 1, i32 1>
+; CHECK-NEXT:    [[Z:%.*]] = or <2 x i32> [[Y]], [[X]]
+; CHECK-NEXT:    [[B:%.*]] = and <2 x i32> [[Z]], <i32 1, i32 1>
+; CHECK-NEXT:    ret <2 x i32> [[B]]
+;
+  %y = add <2 x i32> %x, <i32 1, i32 1>
+  %z = or <2 x i32> %y, %x
+  %b = and <2 x i32> %z, <i32 1, i32 1>
+  ret <2 x i32> %b
+}
-- 
2.7.4