| // RUN: %clang_cc1 -S %s -emit-llvm -o - | FileCheck %s |
| // RUN: %clang_cc1 -S %s -emit-llvm -triple i686-unknown-unknown -o - | FileCheck %s |
| // RUN: %clang_cc1 -S %s -emit-llvm -triple x86_64-unknown-unknown -o - | FileCheck %s |
| |
| #include <stdint.h> |
| |
| // This test is meant to verify code that handles the 'p = nullptr + n' idiom |
| // used by some versions of glibc and gcc. This is undefined behavior but |
| // it is intended there to act like a conversion from a pointer-sized integer |
| // to a pointer, and we would like to tolerate that. |
| |
| #define NULLPTRI8 ((int8_t*)0) |
| |
| // This should get the inttoptr instruction. |
| int8_t *test1(intptr_t n) { |
| return NULLPTRI8 + n; |
| } |
| // CHECK-LABEL: test1 |
| // CHECK: inttoptr |
| // CHECK-NOT: getelementptr |
| |
| // This doesn't meet the idiom because the element type is larger than a byte. |
| int16_t *test2(intptr_t n) { |
| return (int16_t*)0 + n; |
| } |
| // CHECK-LABEL: test2 |
| // CHECK: getelementptr |
| // CHECK-NOT: inttoptr |
| |
| // This doesn't meet the idiom because the offset is subtracted. |
| int8_t* test3(intptr_t n) { |
| return NULLPTRI8 - n; |
| } |
| // CHECK-LABEL: test3 |
| // CHECK: getelementptr |
| // CHECK-NOT: inttoptr |
| |
| // This checks the case where the offset isn't pointer-sized. |
| // The front end will implicitly cast the offset to an integer, so we need to |
| // make sure that doesn't cause problems on targets where integers and pointers |
| // are not the same size. |
| int8_t *test4(int8_t b) { |
| return NULLPTRI8 + b; |
| } |
| // CHECK-LABEL: test4 |
| // CHECK: inttoptr |
| // CHECK-NOT: getelementptr |
