Currently APValues are dumped as a single string. This becomes quickly
completely unreadable since APValue is a tree-like structure. Even a simple
example is not pretty:
struct S { int arr[4]; float f; };
constexpr S s = { .arr = {1,2}, .f = 3.1415f };
// Struct fields: Array: Int: 1, Int: 2, 2 x Int: 0, Float: 3.141500e+00
With this patch this becomes:
-Struct
|-field: Array size=4
| |-elements: Int 1, Int 2
| `-filler: 2 x Int 0
`-field: Float 3.141500e+00
Additionally APValues are currently only dumped as part of visiting a
ConstantExpr. This patch also dump the value of the initializer of constexpr
variable declarations:
constexpr int foo(int a, int b) { return a + b - 42; }
constexpr int a = 1, b = 2;
constexpr int c = foo(a, b) > 0 ? foo(a, b) : foo(b, a);
// VarDecl 0x62100008aec8 <col:3, col:57> col:17 c 'const int' constexpr cinit
// |-value: Int -39
// `-ConditionalOperator 0x62100008b4d0 <col:21, col:57> 'int'
// <snip>
Do the above by moving the dump functions to TextNodeDumper which already has
the machinery to display trees. The cases APValue::LValue, APValue::MemberPointer
and APValue::AddrLabelDiff are left as they were before (unimplemented).
We try to display multiple elements on the same line if they are considered to
be "simple". This is to avoid wasting large amounts of vertical space in an
example like:
constexpr int arr[8] = {0,1,2,3,4,5,6,7};
// VarDecl 0x62100008bb78 <col:3, col:42> col:17 arr 'int const[8]' constexpr cinit
// |-value: Array size=8
// | |-elements: Int 0, Int 1, Int 2, Int 3
// | `-elements: Int 4, Int 5, Int 6, Int 7
Differential Revision: https://reviews.llvm.org/D83183
Reviewed By: aaron.ballman
Summary:
When using ConstantExpr we often need the result of the expression to be kept in the AST. Currently this is done on a by the node that needs the result and has been done multiple times for enumerator, for constexpr variables... . This patch adds to ConstantExpr the ability to store the result of evaluating the expression. no functional changes expected.
Changes:
- Add trailling object to ConstantExpr that can hold an APValue or an uint64_t. the uint64_t is here because most ConstantExpr yield integral values so there is an optimized layout for integral values.
- Add basic* serialization support for the trailing result.
- Move conversion functions from an enum to a fltSemantics from clang::FloatingLiteral to llvm::APFloatBase. this change is to make it usable for serializing APValues.
- Add basic* Import support for the trailing result.
- ConstantExpr created in CheckConvertedConstantExpression now stores the result in the ConstantExpr Node.
- Adapt AST dump to print the result when present.
basic* : None, Indeterminate, Int, Float, FixedPoint, ComplexInt, ComplexFloat,
the result is not yet used anywhere but for -ast-dump.
Reviewers: rsmith, martong, shafik
Reviewed By: rsmith
Subscribers: rnkovacs, hiraditya, dexonsmith, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D62399
llvm-svn: 363493
This moves everything primarily testing the functionality of -ast-dump and -ast-print into their own directory, rather than leaving the tests spread around the testing directory.
llvm-svn: 348017