| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py |
| ; RUN: opt < %s -passes=instcombine -S | FileCheck %s |
| |
| ; Verify that an excessive size to strncmp() isn't truncated to an in-bounds |
| ; value that results in the call being incorrectly folded (as might happen |
| ; when LLVM is compiled in ILP32 mode). |
| |
| declare i32 @strncmp(i8*, i8*, i64) |
| |
| @ax = external global [0 x i8] |
| @bx = external global [0 x i8] |
| |
| @a12345 = constant [5 x i8] c"\01\02\03\04\05" |
| @a123456 = constant [6 x i8] c"\01\02\03\04\05\06" |
| |
| |
| ; Do not fold strncmp(ax, bx, UINT_MAX + (size_t)1) to 0. |
| |
| define i32 @call_strncmp_ax_bx_uimax_p1() { |
| ; CHECK-LABEL: @call_strncmp_ax_bx_uimax_p1( |
| ; CHECK-NEXT: [[RES:%.*]] = call i32 @strncmp(i8* noundef nonnull dereferenceable(1) getelementptr inbounds ([0 x i8], [0 x i8]* @ax, i64 0, i64 0), i8* noundef nonnull dereferenceable(1) getelementptr inbounds ([0 x i8], [0 x i8]* @bx, i64 0, i64 0), i64 4294967296) |
| ; CHECK-NEXT: ret i32 [[RES]] |
| ; |
| |
| %p1 = getelementptr [0 x i8], [0 x i8]* @ax, i32 0, i32 0 |
| %p2 = getelementptr [0 x i8], [0 x i8]* @bx, i32 0, i32 0 |
| %res = call i32 @strncmp(i8* %p1, i8* %p2, i64 4294967296) |
| ret i32 %res |
| } |
| |
| |
| ; Do not fold strncmp(ax, bx, UINT_MAX + (size_t)2) to *ax - *bx. |
| |
| define i32 @call_strncmp_ax_bx_uimax_p2() { |
| ; CHECK-LABEL: @call_strncmp_ax_bx_uimax_p2( |
| ; CHECK-NEXT: [[RES:%.*]] = call i32 @strncmp(i8* noundef nonnull dereferenceable(1) getelementptr inbounds ([0 x i8], [0 x i8]* @ax, i64 0, i64 0), i8* noundef nonnull dereferenceable(1) getelementptr inbounds ([0 x i8], [0 x i8]* @bx, i64 0, i64 0), i64 4294967296) |
| ; CHECK-NEXT: ret i32 [[RES]] |
| ; |
| |
| %p1 = getelementptr [0 x i8], [0 x i8]* @ax, i32 0, i32 0 |
| %p2 = getelementptr [0 x i8], [0 x i8]* @bx, i32 0, i32 0 |
| %res = call i32 @strncmp(i8* %p1, i8* %p2, i64 4294967296) |
| ret i32 %res |
| } |
| |
| |
| ; Fold strncmp(a12345, a123456, UINT_MAX + (size_t)2) to -1 (and not to 0). |
| |
| define i32 @fold_strncmp_a12345_2_uimax_p2() { |
| ; CHECK-LABEL: @fold_strncmp_a12345_2_uimax_p2( |
| ; CHECK-NEXT: ret i32 -1 |
| ; |
| |
| %p1 = getelementptr [5 x i8], [5 x i8]* @a12345, i32 0, i32 0 |
| %p2 = getelementptr [6 x i8], [6 x i8]* @a123456, i32 0, i32 0 |
| %res = call i32 @strncmp(i8* %p1, i8* %p2, i64 4294967297) |
| ret i32 %res |
| } |
| |
| |
| ; Fold strncmp(a123456, a12345, UINT_MAX + (size_t)3) to +1 (and not to 0). |
| |
| define i32 @fold_strncmp_a12345_2_uimax_p3() { |
| ; CHECK-LABEL: @fold_strncmp_a12345_2_uimax_p3( |
| ; CHECK-NEXT: ret i32 1 |
| ; |
| |
| %p1 = getelementptr [6 x i8], [6 x i8]* @a123456, i32 0, i32 0 |
| %p2 = getelementptr [5 x i8], [5 x i8]* @a12345, i32 0, i32 0 |
| %res = call i32 @strncmp(i8* %p1, i8* %p2, i64 4294967298) |
| ret i32 %res |
| } |