1 // NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py 2 /// Check that the alignment builtins handle array-to-pointer decay 3 // RUN: %clang_cc1 -triple=x86_64-unknown-unknown -o - -emit-llvm %s | FileCheck %s 4 5 extern int func(char *c); 6 7 // CHECK-LABEL: define {{[^@]+}}@test_array() #0 8 // CHECK-NEXT: entry: 9 // CHECK-NEXT: [[BUF:%.*]] = alloca [1024 x i8], align 16 10 // CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds [1024 x i8], [1024 x i8]* [[BUF]], i64 0, i64 44 11 // CHECK-NEXT: [[INTPTR:%.*]] = ptrtoint i8* [[ARRAYIDX]] to i64 12 // CHECK-NEXT: [[ALIGNED_INTPTR:%.*]] = and i64 [[INTPTR]], -16 13 // CHECK-NEXT: [[DIFF:%.*]] = sub i64 [[ALIGNED_INTPTR]], [[INTPTR]] 14 // CHECK-NEXT: [[ALIGNED_RESULT:%.*]] = getelementptr inbounds i8, i8* [[ARRAYIDX]], i64 [[DIFF]] 15 // CHECK-NEXT: [[PTRINT:%.*]] = ptrtoint i8* [[ALIGNED_RESULT]] to i64 16 // CHECK-NEXT: [[MASKEDPTR:%.*]] = and i64 [[PTRINT]], 15 17 // CHECK-NEXT: [[MASKCOND:%.*]] = icmp eq i64 [[MASKEDPTR]], 0 18 // CHECK-NEXT: call void @llvm.assume(i1 [[MASKCOND]]) 19 // CHECK-NEXT: [[CALL:%.*]] = call i32 @func(i8* [[ALIGNED_RESULT]]) 20 // CHECK-NEXT: [[ARRAYIDX1:%.*]] = getelementptr inbounds [1024 x i8], [1024 x i8]* [[BUF]], i64 0, i64 22 21 // CHECK-NEXT: [[INTPTR2:%.*]] = ptrtoint i8* [[ARRAYIDX1]] to i64 22 // CHECK-NEXT: [[OVER_BOUNDARY:%.*]] = add i64 [[INTPTR2]], 31 23 // CHECK-NEXT: [[ALIGNED_INTPTR4:%.*]] = and i64 [[OVER_BOUNDARY]], -32 24 // CHECK-NEXT: [[DIFF5:%.*]] = sub i64 [[ALIGNED_INTPTR4]], [[INTPTR2]] 25 // CHECK-NEXT: [[ALIGNED_RESULT6:%.*]] = getelementptr inbounds i8, i8* [[ARRAYIDX1]], i64 [[DIFF5]] 26 // CHECK-NEXT: [[PTRINT7:%.*]] = ptrtoint i8* [[ALIGNED_RESULT6]] to i64 27 // CHECK-NEXT: [[MASKEDPTR8:%.*]] = and i64 [[PTRINT7]], 31 28 // CHECK-NEXT: [[MASKCOND9:%.*]] = icmp eq i64 [[MASKEDPTR8]], 0 29 // CHECK-NEXT: call void @llvm.assume(i1 [[MASKCOND9]]) 30 // CHECK-NEXT: [[CALL10:%.*]] = call i32 @func(i8* [[ALIGNED_RESULT6]]) 31 // CHECK-NEXT: [[ARRAYIDX11:%.*]] = getelementptr inbounds [1024 x i8], [1024 x i8]* [[BUF]], i64 0, i64 16 32 // CHECK-NEXT: [[SRC_ADDR:%.*]] = ptrtoint i8* [[ARRAYIDX11]] to i64 33 // CHECK-NEXT: [[SET_BITS:%.*]] = and i64 [[SRC_ADDR]], 63 34 // CHECK-NEXT: [[IS_ALIGNED:%.*]] = icmp eq i64 [[SET_BITS]], 0 35 // CHECK-NEXT: [[CONV:%.*]] = zext i1 [[IS_ALIGNED]] to i32 36 // CHECK-NEXT: ret i32 [[CONV]] 37 // 38 int test_array(void) { 39 char buf[1024]; 40 func(__builtin_align_down(&buf[44], 16)); 41 func(__builtin_align_up(&buf[22], 32)); 42 return __builtin_is_aligned(&buf[16], 64); 43 } 44 45 // CHECK-LABEL: define {{[^@]+}}@test_array_should_not_mask() #0 46 // CHECK-NEXT: entry: 47 // CHECK-NEXT: [[BUF:%.*]] = alloca [1024 x i8], align 32 48 // CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds [1024 x i8], [1024 x i8]* [[BUF]], i64 0, i64 64 49 // CHECK-NEXT: [[INTPTR:%.*]] = ptrtoint i8* [[ARRAYIDX]] to i64 50 // CHECK-NEXT: [[ALIGNED_INTPTR:%.*]] = and i64 [[INTPTR]], -16 51 // CHECK-NEXT: [[DIFF:%.*]] = sub i64 [[ALIGNED_INTPTR]], [[INTPTR]] 52 // CHECK-NEXT: [[ALIGNED_RESULT:%.*]] = getelementptr inbounds i8, i8* [[ARRAYIDX]], i64 [[DIFF]] 53 // CHECK-NEXT: [[PTRINT:%.*]] = ptrtoint i8* [[ALIGNED_RESULT]] to i64 54 // CHECK-NEXT: [[MASKEDPTR:%.*]] = and i64 [[PTRINT]], 15 55 // CHECK-NEXT: [[MASKCOND:%.*]] = icmp eq i64 [[MASKEDPTR]], 0 56 // CHECK-NEXT: call void @llvm.assume(i1 [[MASKCOND]]) 57 // CHECK-NEXT: [[CALL:%.*]] = call i32 @func(i8* [[ALIGNED_RESULT]]) 58 // CHECK-NEXT: [[ARRAYIDX1:%.*]] = getelementptr inbounds [1024 x i8], [1024 x i8]* [[BUF]], i64 0, i64 32 59 // CHECK-NEXT: [[INTPTR2:%.*]] = ptrtoint i8* [[ARRAYIDX1]] to i64 60 // CHECK-NEXT: [[OVER_BOUNDARY:%.*]] = add i64 [[INTPTR2]], 31 61 // CHECK-NEXT: [[ALIGNED_INTPTR4:%.*]] = and i64 [[OVER_BOUNDARY]], -32 62 // CHECK-NEXT: [[DIFF5:%.*]] = sub i64 [[ALIGNED_INTPTR4]], [[INTPTR2]] 63 // CHECK-NEXT: [[ALIGNED_RESULT6:%.*]] = getelementptr inbounds i8, i8* [[ARRAYIDX1]], i64 [[DIFF5]] 64 // CHECK-NEXT: [[PTRINT7:%.*]] = ptrtoint i8* [[ALIGNED_RESULT6]] to i64 65 // CHECK-NEXT: [[MASKEDPTR8:%.*]] = and i64 [[PTRINT7]], 31 66 // CHECK-NEXT: [[MASKCOND9:%.*]] = icmp eq i64 [[MASKEDPTR8]], 0 67 // CHECK-NEXT: call void @llvm.assume(i1 [[MASKCOND9]]) 68 // CHECK-NEXT: [[CALL10:%.*]] = call i32 @func(i8* [[ALIGNED_RESULT6]]) 69 // CHECK-NEXT: ret i32 1 70 // 71 int test_array_should_not_mask(void) { 72 _Alignas(32) char buf[1024]; 73 // TODO: The align_up and align_down calls should be folded to no-ops 74 func(__builtin_align_down(&buf[64], 16)); 75 func(__builtin_align_up(&buf[32], 32)); 76 // This expression can be constant-evaluated: 77 return __builtin_is_aligned(&buf[64], 32); 78 } 79