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1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py2; RUN: opt < %s -passes=instcombine -S | FileCheck %s3 4; Verify that an excessive size to strncmp() isn't truncated to an in-bounds5; value that results in the call being incorrectly folded (as might happen6; when LLVM is compiled in ILP32 mode).7 8declare i32 @strncmp(ptr, ptr, i64)9 10@ax = external global [0 x i8]11@bx = external global [0 x i8]12 13@a12345 = constant [5 x i8] c"\01\02\03\04\05"14@a123456 = constant [6 x i8] c"\01\02\03\04\05\06"15 16 17; Do not fold strncmp(ax, bx, UINT_MAX + (size_t)1) to 0.18 19define i32 @call_strncmp_ax_bx_uimax_p1() {20; CHECK-LABEL: @call_strncmp_ax_bx_uimax_p1(21; CHECK-NEXT: [[RES:%.*]] = call i32 @strncmp(ptr noundef nonnull dereferenceable(1) @ax, ptr noundef nonnull dereferenceable(1) @bx, i64 4294967296)22; CHECK-NEXT: ret i32 [[RES]]23;24 25 %res = call i32 @strncmp(ptr @ax, ptr @bx, i64 4294967296)26 ret i32 %res27}28 29 30; Do not fold strncmp(ax, bx, UINT_MAX + (size_t)2) to *ax - *bx.31 32define i32 @call_strncmp_ax_bx_uimax_p2() {33; CHECK-LABEL: @call_strncmp_ax_bx_uimax_p2(34; CHECK-NEXT: [[RES:%.*]] = call i32 @strncmp(ptr noundef nonnull dereferenceable(1) @ax, ptr noundef nonnull dereferenceable(1) @bx, i64 4294967296)35; CHECK-NEXT: ret i32 [[RES]]36;37 38 %res = call i32 @strncmp(ptr @ax, ptr @bx, i64 4294967296)39 ret i32 %res40}41 42 43; Fold strncmp(a12345, a123456, UINT_MAX + (size_t)2) to -1 (and not to 0).44 45define i32 @fold_strncmp_a12345_2_uimax_p2() {46; CHECK-LABEL: @fold_strncmp_a12345_2_uimax_p2(47; CHECK-NEXT: ret i32 -148;49 50 %res = call i32 @strncmp(ptr @a12345, ptr @a123456, i64 4294967297)51 ret i32 %res52}53 54 55; Fold strncmp(a123456, a12345, UINT_MAX + (size_t)3) to +1 (and not to 0).56 57define i32 @fold_strncmp_a12345_2_uimax_p3() {58; CHECK-LABEL: @fold_strncmp_a12345_2_uimax_p3(59; CHECK-NEXT: ret i32 160;61 62 %res = call i32 @strncmp(ptr @a123456, ptr @a12345, i64 4294967298)63 ret i32 %res64}65