LLVM 1.5 Release Notes
  1. Introduction
  2. What's New?
  3. Installation Instructions
  4. Portability and Supported Platforms
  5. Known Problems
  6. Additional Information

Written by the LLVM Team

Introduction

This document contains the release notes for the LLVM compiler infrastructure, release 1.5. Here we describe the status of LLVM, including any known problems and improvements from the previous release. The most up-to-date version of this document can be found on the LLVM 1.5 web site. If you are not reading this on the LLVM web pages, you should probably go there because this document may be updated after the release.

For more information about LLVM, including information about the latest release, please check out the main LLVM web site. If you have questions or comments, the LLVM developer's mailing list is a good place to send them.

Note that if you are reading this file from CVS or the main LLVM web page, this document applies to the next release, not the current one. To see the release notes for the current or previous releases, see the releases page.

What's New?

This is the sixth public release of the LLVM compiler infrastructure.

At this time, LLVM is known to correctly compile a broad range of C and C++ programs, including the SPEC CPU95 & 2000 suite. TODO. It also includes bug fixes for those problems found since the 1.4 release.

This release implements the following new features:
  1. LLVM now includes an Interprocedural Sparse Conditional Constant Propagation pass, named -ipsccp, which is run by default at link-time.
  2. LLVM 1.5 is now about 15% faster than LLVM 1.4 and its core data structures use about 30% less memory.
  3. LLVM includes new experimental native code generators for SparcV8, Alpha, and IA64.
  4. Support for Microsoft Visual Studio is improved, and now documented.
  5. Configuring LLVM to build targets selectively is now implemented, via the --enable-targets= option. This feature is documented here.
  6. LLVM now supports custom and target-specific calling conventions.
In this release, the following missing features were implemented:
  1. LLVM can now create native shared libraries with 'llvm-gcc ... -shared -Wl,-native' (or with -Wl,-native-cbe).
  2. LLVM now supports a new "llvm.prefetch " intrinsic, and llvm-gcc now supports __builtin_prefetch.
  3. LLVM now supports intrinsics for bit counting and llvm-gcc now implements the GCC __builtin_popcount, __builtin_ctz, and __builtin_clz builtins.
In this release, the following Quality of Implementation issues were fixed:
  1. Building LLVM in optimized mode should no longer cause GCC to hit swap in the PowerPC backend.
This release includes the following Code Quality improvements:
  1. Transition code for 1.0 style varargs was removed.
In this release, the following bugs in the previous release were fixed:

Bugs fixed in the LLVM Core:

  1. [dse] DSE deletes stores that are partially overwritten by smaller stores
  2. [instcombine] miscompilation of setcc or setcc in one case

Code Generator Bugs:

  1. [cbackend] Logical constant expressions (and/or/xor) not implemented
  2. [cbackend] C backend does not respect 'volatile'

Bugs in the C/C++ front-end:

  1. [llvmgcc] llvm-gcc incorrectly rejects some constant initializers involving the addresses of array elements
  2. [llvm-g++] Crash compiling anonymous union
  3. [llvm-g++] Do not use dynamic initialization where static init will do
  4. [llvmgcc] Field offset miscalculated for some structure fields following bit fields
  5. [llvm-g++] Temporary lifetimes incorrect for short circuit logical operations
  6. [llvm-gcc] Crash compiling bitfield <-> aggregate assignment
  7. [llvm-g++] Error compiling virtual function thunk with an unnamed argument
  8. [llvm-gcc] Crash on certain C99 complex number routines
  9. [llvm-g++] Crash using placement new on an array type
Portability and Supported Platforms

LLVM is known to work on the following platforms:

The core LLVM infrastructure uses GNU autoconf to adapt itself to the machine and operating system on which it is built. However, minor porting may be required to get LLVM to work on new platforms. We welcome your portability patches and reports of successful builds or error messages.

Known Problems

This section contains all known problems with the LLVM system, listed by component. As new problems are discovered, they will be added to these sections. If you run into a problem, please check the LLVM bug database and submit a bug if there isn't already one.

Experimental features included with this release

The following components of this LLVM release are either untested, known to be broken or unreliable, or are in early development. These components should not be relied on, and bugs should not be filed against them, but they may be useful to some people. In particular, if you would like to work on one of these components, please contact us on the llvmdev list.

Known problems with the LLVM Core
Known problems with the C front-end
Bugs
Notes

If you run into GCC extensions which have not been included in any of these lists, please let us know (also including whether or not they work).

Known problems with the C++ front-end

For this release, the C++ front-end is considered to be fully tested and works for a number of non-trivial programs, including LLVM itself.

Bugs
Notes
Known problems with the X86 back-end
Known problems with the SparcV9 back-end
Known problems with the PowerPC back-end
Known problems with the C back-end
Known problems with the Alpha back-end
Additional Information

A wide variety of additional information is available on the LLVM web page, including mailing lists and publications describing algorithms and components implemented in LLVM. The web page also contains versions of the API documentation which is up-to-date with the CVS version of the source code. You can access versions of these documents specific to this release by going into the "llvm/doc/" directory in the LLVM tree.

If you have any questions or comments about LLVM, please feel free to contact us via the mailing lists.


Valid CSS! Valid HTML 4.01! The LLVM Compiler Infrastructure
Last modified: $Date$