[cfe-dev] assert when vector variable is used as the size of array

[Anton Yartsev]

Hi all,

I accidentally stumbled upon the fact that situation when a vector 
variable is used as the size of array is not handled. Compiling the code

void f()
{
   int __attribute__ ((vector_size (16))) a;
   int b[a];
}

ends with

Assertion failed: castIsValid(getOpcode(), S, Ty) && "Illegal BitCast", 
file Instructions.cpp, line 2654

While investigating the problem I found out that methods 
Type::isIntegerType(), Type::isSignedIntegerType() and 
Type::isUnsignedIntegerType() (.\lib\AST\Type.cpp ) return 'true' for 
vector types with corresponding element types. It looks strange as 
vector types are not treated as integer types.
I made two patches: the first one - vector_size_of_array.patch - removes 
code for vectors from the above methods and adds additional methods 
instead - Type::hasIntegerRepresentation(), 
Type::hasSignedIntRepresentation() and 
Type::hasUnsignedIntRepresentation() - by analogy with 
Type::isFloatingType() and Type::hasFloatingRepresentation(). Calls to 
old methods were replaced with calls to new ones where it was needed (at 
least no regression bugs). The patch solves the subject. It also make 
Clang sliiiightly faster..
The second patch - vector_size_of_array_SIMPLE.patch - only solves the 
subject.
Please review and comment.

-- 
Anton

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