summaryrefslogtreecommitdiff
path: root/test/Transforms/InstCombine/icmp-add.ll
diff options
context:
space:
mode:
Diffstat (limited to 'test/Transforms/InstCombine/icmp-add.ll')
-rw-r--r--test/Transforms/InstCombine/icmp-add.ll247
1 files changed, 247 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/icmp-add.ll b/test/Transforms/InstCombine/icmp-add.ll
new file mode 100644
index 000000000000..efeb9d5bb45b
--- /dev/null
+++ b/test/Transforms/InstCombine/icmp-add.ll
@@ -0,0 +1,247 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+; PR1949
+
+define i1 @test1(i32 %a) {
+; CHECK-LABEL: @test1(
+; CHECK-NEXT: [[C:%.*]] = icmp ugt i32 %a, -5
+; CHECK-NEXT: ret i1 [[C]]
+;
+ %b = add i32 %a, 4
+ %c = icmp ult i32 %b, 4
+ ret i1 %c
+}
+
+define <2 x i1> @test1vec(<2 x i32> %a) {
+; CHECK-LABEL: @test1vec(
+; CHECK-NEXT: [[C:%.*]] = icmp ugt <2 x i32> %a, <i32 -5, i32 -5>
+; CHECK-NEXT: ret <2 x i1> [[C]]
+;
+ %b = add <2 x i32> %a, <i32 4, i32 4>
+ %c = icmp ult <2 x i32> %b, <i32 4, i32 4>
+ ret <2 x i1> %c
+}
+
+define i1 @test2(i32 %a) {
+; CHECK-LABEL: @test2(
+; CHECK-NEXT: [[C:%.*]] = icmp ult i32 %a, 4
+; CHECK-NEXT: ret i1 [[C]]
+;
+ %b = sub i32 %a, 4
+ %c = icmp ugt i32 %b, -5
+ ret i1 %c
+}
+
+define <2 x i1> @test2vec(<2 x i32> %a) {
+; CHECK-LABEL: @test2vec(
+; CHECK-NEXT: [[C:%.*]] = icmp ult <2 x i32> %a, <i32 4, i32 4>
+; CHECK-NEXT: ret <2 x i1> [[C]]
+;
+ %b = sub <2 x i32> %a, <i32 4, i32 4>
+ %c = icmp ugt <2 x i32> %b, <i32 -5, i32 -5>
+ ret <2 x i1> %c
+}
+
+define i1 @test3(i32 %a) {
+; CHECK-LABEL: @test3(
+; CHECK-NEXT: [[C:%.*]] = icmp sgt i32 %a, 2147483643
+; CHECK-NEXT: ret i1 [[C]]
+;
+ %b = add i32 %a, 4
+ %c = icmp slt i32 %b, 2147483652
+ ret i1 %c
+}
+
+define <2 x i1> @test3vec(<2 x i32> %a) {
+; CHECK-LABEL: @test3vec(
+; CHECK-NEXT: [[C:%.*]] = icmp sgt <2 x i32> %a, <i32 2147483643, i32 2147483643>
+; CHECK-NEXT: ret <2 x i1> [[C]]
+;
+ %b = add <2 x i32> %a, <i32 4, i32 4>
+ %c = icmp slt <2 x i32> %b, <i32 2147483652, i32 2147483652>
+ ret <2 x i1> %c
+}
+
+define i1 @test4(i32 %a) {
+; CHECK-LABEL: @test4(
+; CHECK-NEXT: [[C:%.*]] = icmp slt i32 %a, -4
+; CHECK-NEXT: ret i1 [[C]]
+;
+ %b = add i32 %a, 2147483652
+ %c = icmp sge i32 %b, 4
+ ret i1 %c
+}
+
+define <2 x i1> @test4vec(<2 x i32> %a) {
+; CHECK-LABEL: @test4vec(
+; CHECK-NEXT: [[C:%.*]] = icmp slt <2 x i32> %a, <i32 -4, i32 -4>
+; CHECK-NEXT: ret <2 x i1> [[C]]
+;
+ %b = add <2 x i32> %a, <i32 2147483652, i32 2147483652>
+ %c = icmp sge <2 x i32> %b, <i32 4, i32 4>
+ ret <2 x i1> %c
+}
+
+; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
+; This becomes equality because it's at the limit.
+
+define i1 @nsw_slt1(i8 %a) {
+; CHECK-LABEL: @nsw_slt1(
+; CHECK-NEXT: [[C:%.*]] = icmp eq i8 %a, -128
+; CHECK-NEXT: ret i1 [[C]]
+;
+ %b = add nsw i8 %a, 100
+ %c = icmp slt i8 %b, -27
+ ret i1 %c
+}
+
+; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
+; This becomes equality because it's at the limit.
+
+define i1 @nsw_slt2(i8 %a) {
+; CHECK-LABEL: @nsw_slt2(
+; CHECK-NEXT: [[C:%.*]] = icmp ne i8 %a, 127
+; CHECK-NEXT: ret i1 [[C]]
+;
+ %b = add nsw i8 %a, -100
+ %c = icmp slt i8 %b, 27
+ ret i1 %c
+}
+
+; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
+; Less than the limit, so the predicate doesn't change.
+
+define i1 @nsw_slt3(i8 %a) {
+; CHECK-LABEL: @nsw_slt3(
+; CHECK-NEXT: [[C:%.*]] = icmp slt i8 %a, -126
+; CHECK-NEXT: ret i1 [[C]]
+;
+ %b = add nsw i8 %a, 100
+ %c = icmp slt i8 %b, -26
+ ret i1 %c
+}
+
+; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
+; Less than the limit, so the predicate doesn't change.
+
+define i1 @nsw_slt4(i8 %a) {
+; CHECK-LABEL: @nsw_slt4(
+; CHECK-NEXT: [[C:%.*]] = icmp slt i8 %a, 126
+; CHECK-NEXT: ret i1 [[C]]
+;
+ %b = add nsw i8 %a, -100
+ %c = icmp slt i8 %b, 26
+ ret i1 %c
+}
+
+; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
+; Try sgt to make sure that works too.
+
+define i1 @nsw_sgt1(i8 %a) {
+; CHECK-LABEL: @nsw_sgt1(
+; CHECK-NEXT: [[C:%.*]] = icmp eq i8 %a, 127
+; CHECK-NEXT: ret i1 [[C]]
+;
+ %b = add nsw i8 %a, -100
+ %c = icmp sgt i8 %b, 26
+ ret i1 %c
+}
+
+; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
+; Try a vector type to make sure that works too.
+; FIXME: This should be 'eq 127' as above.
+
+define <2 x i1> @nsw_sgt2_splat_vec(<2 x i8> %a) {
+; CHECK-LABEL: @nsw_sgt2_splat_vec(
+; CHECK-NEXT: [[C:%.*]] = icmp sgt <2 x i8> %a, <i8 -126, i8 -126>
+; CHECK-NEXT: ret <2 x i1> [[C]]
+;
+ %b = add nsw <2 x i8> %a, <i8 100, i8 100>
+ %c = icmp sgt <2 x i8> %b, <i8 -26, i8 -26>
+ ret <2 x i1> %c
+}
+
+; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
+; Comparison with 0 doesn't need special-casing.
+
+define i1 @slt_zero_add_nsw(i32 %a) {
+; CHECK-LABEL: @slt_zero_add_nsw(
+; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 %a, -1
+; CHECK-NEXT: ret i1 [[CMP]]
+;
+ %add = add nsw i32 %a, 1
+ %cmp = icmp slt i32 %add, 0
+ ret i1 %cmp
+}
+
+; The same fold should work with vectors.
+
+define <2 x i1> @slt_zero_add_nsw_splat_vec(<2 x i8> %a) {
+; CHECK-LABEL: @slt_zero_add_nsw_splat_vec(
+; CHECK-NEXT: [[CMP:%.*]] = icmp slt <2 x i8> %a, <i8 -1, i8 -1>
+; CHECK-NEXT: ret <2 x i1> [[CMP]]
+;
+ %add = add nsw <2 x i8> %a, <i8 1, i8 1>
+ %cmp = icmp slt <2 x i8> %add, zeroinitializer
+ ret <2 x i1> %cmp
+}
+
+; Test the edges - instcombine should not interfere with simplification to constants.
+; Constant subtraction does not overflow, but this is false.
+
+define i1 @nsw_slt3_ov_no(i8 %a) {
+; CHECK-LABEL: @nsw_slt3_ov_no(
+; CHECK-NEXT: ret i1 false
+;
+ %b = add nsw i8 %a, 100
+ %c = icmp slt i8 %b, -28
+ ret i1 %c
+}
+
+; Test the edges - instcombine should not interfere with simplification to constants.
+; Constant subtraction overflows. This is false.
+
+define i1 @nsw_slt4_ov(i8 %a) {
+; CHECK-LABEL: @nsw_slt4_ov(
+; CHECK-NEXT: ret i1 false
+;
+ %b = add nsw i8 %a, 100
+ %c = icmp slt i8 %b, -29
+ ret i1 %c
+}
+
+; Test the edges - instcombine should not interfere with simplification to constants.
+; Constant subtraction overflows. This is true.
+
+define i1 @nsw_slt5_ov(i8 %a) {
+; CHECK-LABEL: @nsw_slt5_ov(
+; CHECK-NEXT: ret i1 true
+;
+ %b = add nsw i8 %a, -100
+ %c = icmp slt i8 %b, 28
+ ret i1 %c
+}
+
+; InstCombine should not thwart this opportunity to simplify completely.
+
+define i1 @slt_zero_add_nsw_signbit(i8 %x) {
+; CHECK-LABEL: @slt_zero_add_nsw_signbit(
+; CHECK-NEXT: ret i1 true
+;
+ %y = add nsw i8 %x, -128
+ %z = icmp slt i8 %y, 0
+ ret i1 %z
+}
+
+; InstCombine should not thwart this opportunity to simplify completely.
+
+define i1 @slt_zero_add_nuw_signbit(i8 %x) {
+; CHECK-LABEL: @slt_zero_add_nuw_signbit(
+; CHECK-NEXT: ret i1 true
+;
+ %y = add nuw i8 %x, 128
+ %z = icmp slt i8 %y, 0
+ ret i1 %z
+}
+
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-18 21:50:16 +0000