Precommit test for D144777, NFC

Signed-off-by: Jun Zhang <jun@junz.org>

diff --git a/llvm/test/Transforms/InstCombine/fold-signbit-test-power2.ll b/llvm/test/Transforms/InstCombine/fold-signbit-test-power2.ll
new file mode 100644 (file)
index 0000000..8c51209
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/fold-signbit-test-power2.ll
@@ -0,0 +1,119 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -passes=instcombine -S | FileCheck %s
+
+; icmp slt (and X, -X), 0 --> icmp eq (X, MinSignC)
+define i1 @pow2_or_zero1(i8 %x) {
+; CHECK-LABEL: @pow2_or_zero1(
+; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X:%.*]]
+; CHECK-NEXT:    [[POW2_OR_ZERO:%.*]] = and i8 [[NEG]], [[X]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i8 [[POW2_OR_ZERO]], 0
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %neg = sub i8 0, %x
+  %pow2_or_zero = and i8 %x, %neg
+  %cmp = icmp slt i8 %pow2_or_zero, 0
+  ret i1 %cmp
+}
+
+; icmp slt (and -X, X), 0 --> icmp eq (X, MinSignC)
+define i1 @pow2_or_zero1_commute(i8 %A) {
+; CHECK-LABEL: @pow2_or_zero1_commute(
+; CHECK-NEXT:    [[X:%.*]] = sdiv i8 42, [[A:%.*]]
+; CHECK-NEXT:    [[NEG:%.*]] = sub nsw i8 0, [[X]]
+; CHECK-NEXT:    [[POW2_OR_ZERO:%.*]] = and i8 [[X]], [[NEG]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i8 [[POW2_OR_ZERO]], 0
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %x = sdiv i8 42, %A ; thwart complexity-based canonicalization
+  %neg = sub i8 0, %x
+  %pow2_or_zero = and i8 %neg, %x
+  %cmp = icmp slt i8 %pow2_or_zero, 0
+  ret i1 %cmp
+}
+
+define <2 x i1> @pow2_or_zero1_vec(<2 x i8> %x) {
+; CHECK-LABEL: @pow2_or_zero1_vec(
+; CHECK-NEXT:    [[NEG:%.*]] = sub <2 x i8> zeroinitializer, [[X:%.*]]
+; CHECK-NEXT:    [[POW2_OR_ZERO:%.*]] = and <2 x i8> [[NEG]], [[X]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt <2 x i8> [[POW2_OR_ZERO]], zeroinitializer
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %neg = sub <2 x i8> <i8 0, i8 0>, %x
+  %pow2_or_zero = and <2 x i8> %x, %neg
+  %cmp = icmp slt <2 x i8> %pow2_or_zero, <i8 0, i8 0>
+  ret <2 x i1> %cmp
+}
+
+
+define <2 x i1> @pow2_or_zero1_vec_commute(<2 x i8> %A) {
+; CHECK-LABEL: @pow2_or_zero1_vec_commute(
+; CHECK-NEXT:    [[X:%.*]] = mul <2 x i8> [[A:%.*]], <i8 42, i8 42>
+; CHECK-NEXT:    [[NEG:%.*]] = sub <2 x i8> zeroinitializer, [[X]]
+; CHECK-NEXT:    [[POW2_OR_ZERO:%.*]] = and <2 x i8> [[X]], [[NEG]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt <2 x i8> [[POW2_OR_ZERO]], zeroinitializer
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %x = mul <2 x i8> <i8 42, i8 42>, %A ; thwart complexity-based canonicalization
+  %neg = sub <2 x i8> <i8 0, i8 0>, %x
+  %pow2_or_zero = and <2 x i8> %neg, %x
+  %cmp = icmp slt <2 x i8> %pow2_or_zero, <i8 0, i8 0>
+  ret <2 x i1> %cmp
+}
+
+; icmp sgt (and X, -X), -1 --> icmp ne (X, MinSignC)
+define i1 @pow2_or_zero2(i8 %x) {
+; CHECK-LABEL: @pow2_or_zero2(
+; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X:%.*]]
+; CHECK-NEXT:    [[POW2_OR_ZERO:%.*]] = and i8 [[NEG]], [[X]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i8 [[POW2_OR_ZERO]], -1
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %neg = sub i8 0, %x
+  %pow2_or_zero = and i8 %x, %neg
+  %cmp = icmp sgt i8 %pow2_or_zero, -1
+  ret i1 %cmp
+}
+
+; icmp sgt (and -X, X), -1 --> icmp ne (X, MinSignC)
+define i1 @pow2_or_zero2_commute(i8 %A) {
+; CHECK-LABEL: @pow2_or_zero2_commute(
+; CHECK-NEXT:    [[X:%.*]] = mul i8 [[A:%.*]], 42
+; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X]]
+; CHECK-NEXT:    [[POW2_OR_ZERO:%.*]] = and i8 [[X]], [[NEG]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i8 [[POW2_OR_ZERO]], -1
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %x = mul i8 42, %A ; thwart complexity-based canonicalization
+  %neg = sub i8 0, %x
+  %pow2_or_zero = and i8 %neg, %x
+  %cmp = icmp sgt i8 %pow2_or_zero, -1
+  ret i1 %cmp
+}
+
+define <2 x i1> @pow2_or_zero2_vec(<2 x i8> %x) {
+; CHECK-LABEL: @pow2_or_zero2_vec(
+; CHECK-NEXT:    [[NEG:%.*]] = sub <2 x i8> zeroinitializer, [[X:%.*]]
+; CHECK-NEXT:    [[POW2_OR_ZERO:%.*]] = and <2 x i8> [[NEG]], [[X]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt <2 x i8> [[POW2_OR_ZERO]], <i8 -1, i8 -1>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %neg = sub <2 x i8> <i8 0, i8 0>, %x
+  %pow2_or_zero = and <2 x i8> %x, %neg
+  %cmp = icmp sgt <2 x i8> %pow2_or_zero, <i8 -1, i8 -1>
+  ret <2 x i1> %cmp
+}
+
+define <2 x i1> @pow2_or_zero2_vec_commute(<2 x i8> %A) {
+; CHECK-LABEL: @pow2_or_zero2_vec_commute(
+; CHECK-NEXT:    [[X:%.*]] = mul <2 x i8> [[A:%.*]], <i8 42, i8 42>
+; CHECK-NEXT:    [[NEG:%.*]] = sub <2 x i8> zeroinitializer, [[X]]
+; CHECK-NEXT:    [[POW2_OR_ZERO:%.*]] = and <2 x i8> [[X]], [[NEG]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt <2 x i8> [[POW2_OR_ZERO]], <i8 -1, i8 -1>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %x = mul <2 x i8> <i8 42, i8 42>, %A ; thwart complexity-based canonicalization
+  %neg = sub <2 x i8> <i8 0, i8 0>, %x
+  %pow2_or_zero = and <2 x i8> %neg, %x
+  %cmp = icmp sgt <2 x i8> %pow2_or_zero, <i8 -1, i8 -1>
+  ret <2 x i1> %cmp
+}