[LLVMdev] n-bit bytes for clang/llvm

Patrik Hägglund H
Tue, 10 Mar 2015 10:34:12 -0000

As written in the threads shown below, we maintain LLVM patches for 16-bit
bytes.

http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-September/076603.html
http://lists.cs.uiuc.edu/pipermail/llvmdev/2015-March/083157.html

/Patrik Hägglund

From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at cs.uiuc.edu] On
Behalf Of Tyro Software
Sent: den 10 mars 2015 11:12
To: llvmdev at cs.uiuc.edu
Subject: [LLVMdev] n-bit bytes for clang/llvm

Back in 2009 there was some discussion of the practicality of supporting char
sizes greater than 8-bit:

http://lists.cs.uiuc.edu/pipermail/cfe-dev/2009-September/thread.html#6349
http://lists.cs.uiuc.edu/pipermail/llvmdev/2009-September/thread.html#26025

with the consensus seemingly being "quite doable, please get a good patch
and submit".

However the current code appears (to my neophyte eyes) to be explicitly 8-bit,
e.g. one instance called out in the mail thread remains:

/// isString - This method returns true if this is an array of i8.
bool ConstantDataSequential::isString() const {
  return isa<ArrayType>(getType()) &&
getElementType()->isIntegerTy(8);
}

I didn't find anything related beyond this mail thread such as a discussion
of a patch but of course I might be searching too narrowly - perhaps someone
here can recall whether it went any further, whether insurmountable barriers do
exist, etc?