X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=docs%2FReleaseNotes.html;h=d1759f1c539b26575e10168051abadd05aec3950;hb=6568fe876c4b3b2f1ee9f326b52369a9b5c944b2;hp=121ce140f095346ad52e295a8618086f1eb20098;hpb=98328745041aa3c352796347d89cd62d5b6ab808;p=oota-llvm.git diff --git a/docs/ReleaseNotes.html b/docs/ReleaseNotes.html index 121ce140f09..d1759f1c539 100644 --- a/docs/ReleaseNotes.html +++ b/docs/ReleaseNotes.html @@ -3,33 +3,33 @@ - LLVM 1.2 Release Notes + LLVM 1.3 Release Notes -
- LLVM 1.2 Release Notes -
+
LLVM 1.3 Release Notes
  1. Introduction
  2. What's New?
    3. +
  3. Installation Instructions
  4. Portability and Supported Platforms
    5. -
  5. Installation Instructions
  6. Known Problems
  7. Additional Information
-
-

Written by the LLVM team

+

+

Written by the LLVM team

@@ -41,10 +41,10 @@

This document contains the release notes for the LLVM compiler -infrastructure, release 1.2. Here we describe the status of LLVM, including any +infrastructure, release 1.3. Here we describe the status of LLVM, including any known problems and bug fixes from the previous release. The most up-to-date version of this document can be found on the LLVM 1.2 web site. If you are +href="http://llvm.cs.uiuc.edu/releases/1.3/">LLVM 1.3 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.

@@ -69,133 +69,246 @@ href="http://llvm.cs.uiuc.edu/releases/">releases page.

-

This is the third public release of the LLVM compiler infrastructure. -

+

This is the fourth public release of the LLVM compiler infrastructure. This +release primarily improves the performance of the +code produced by all aspects of the LLVM compiler and adds many new features, and fixes a few +bugs as well.

-

At this time, LLVM is known to correctly compile and run all C -& C++ SPEC CPU2000 benchmarks, the Olden benchmarks, and the Ptrdist -benchmarks. It has also been used to compile many other programs. LLVM -now also works with a broad variety of C++ programs, though it has still -received less testing than the C front-end. -

+

At this time, LLVM is known to correctly compile and run all C & C++ +SPEC CPU2000 benchmarks, the Olden benchmarks, and the Ptrdist benchmarks. It +has also been used to compile many other programs. LLVM now also works +with a broad variety of C++ programs, though it has still received less testing +than the C front-end.

+
-This release implements the following new features: +This release implements the following new features:
+
+
    -
  1. A new LLVM source-level debugger has been started.
    2. -
  2. +
  3. The LLVM select instruction is +now fully implemented and supported by all transformations, native code +generators, and the interpreter.
    4. +
  4. Bugpoint can now narrow down code-generation bugs to a loop nest, where +before it could only narrow them down to a function being miscompiled.
    5. +
  5. Bugpoint can now debug arbitrary +modes of llc and lli, by passing them command line flags (e.g., +-regalloc=linearscan, -enable-correct-eh-support, etc.)
    6. +
  6. The Control Flow Graph in the native code generators is no longer +constrained to be the same as the CFG for the LLVM input code.
    7. +
  7. The LLVM induction variable analysis routines have been rewritten.
    8. +
  8. LLVM now has new loop unrolling and loop unswitching passes.
    9. +
  9. The induction variable substitution pass performs linear function test +replacement and exit value replacement optimizations.
    10. +
  10. LLVM now has first-class support for Accurate Garbage Collection, enabling the use +of aggressive copying and generational collectors.
    11. +
  11. LLVM now includes an implementation of Andersen's interprocedural alias +analysis algorithm.
    12. +
  12. Bugpoint can extract individual +basic blocks to track down reduce miscompilation testcases.
    13. +
  13. LLVM and the C front-end now work under Win32 using the +Cygwin runtime libraries. +This includes the JIT compiler.
    14. +
  14. The LLVM code generator is now being documented.
    15. +
  15. There is a new tool, llvm-bcanalyzer. This tool can compute basic +statistics and bytecode density statistics on a module or function basis and +also dump out bytecode in a textual format that is lower level than assembly +(values are not resolved from slot numbers). It should only be of interest to +(a) those who are working to improve the bytecode format and (b) those who +really want to understand or document the details of the bytecode format.
    16. +
  16. The LLVM Bytecode file format is now +documented.
    17. +
  17. LLVM now provides an llvm.isunordered intrinsic for efficient +implementation of unordered floating point comparisons.
    18. +
  18. The llvmgcc front-end now supports the GCC builtins for ISO C99 floating +point comparison macros (e.g., __builtin_islessequal).
    19. +
  19. Now that there are more source files than can fit on a 32Kbyte command +line (Linux's limit), there's a new utility for searching the sources. The +llvmgrep tool in the utils directory combines an egrep and a find without +passing filenames through the command line. This improves performance +slightly. Simply run llvmgrep like you might egrep but leave off the file +names.
    20. +
  20. We now generate HTML documentation and man pages for the tools from a single +source (perl-style POD files).
    21. +
  21. The LLVM code generator can now dynamically load targets from shared +objects.
+
+
In this release, the following missing features were implemented:
+
+
    -
  1. Exception handling support in the X86 -& Sparc native code generators
    2. -
  2. The C/C++ front-end now support the GCC __builtin_return_address and __builtin_frame_address extensions.
    3. +
  3. LLVM cannot handle structures with +more than 256 elements
    4. +
  4. [bugpoint] External functions used in +non-instruction entities, such as global constant initializer
    5. +
  5. Stacker does not handle targets +with 64-bit pointers.
    6. +
  6. Bugpoint doesn't support +uses of external fns by immediate constant exprs
+
-In this release, the following Quality of Implementation issues were fixed: +In this release, the following Quality of Implementation +issues were fixed:
-
    +
    -
  1. JIT should lazily initialize global variables
    2. -
  2. [X86] X86 Backend never releases memory for machine code structures
    3. -
  3. [vmcore] OpaqueType objects memory leak
    4. -
  4. [llvmgcc] C front-end does not compile "extern inline" into linkonce
    5. -
  5. Bytecode format inconsistent
    6. -
  6. [loadvn/inline/scalarrepl] Slow optimizations with extremely large basic blocks
    7. -
  7. [asmparser] Really slow parsing of types with complex upreferences
    8. -
  8. [llvmgcc] C front-end does not emit 'zeroinitializer' when possible
    9. -
  9. LLVM is now much more memory efficient when handling large zero initialized arrays
    10. +
      +
    1. LLVM tools will happily spew +bytecode onto your terminal
      2. +
    2. [llvmgcc] type names are not emitted +for structure typedefs
      3. +
    3. All documentation is now conformant to the HTML 4.01 (Strict) level.
      4. +
    4. The spurious "WARNING: Found global types that are not compatible" warning +produced when linking C++ programs has been fixed.
      5. +
    5. lli Doesn't Handle Exceptions From +Bytecode Reader
      6. +
    6. operator<< on a Value* now prints the address of the object instead of its contents.
      7. +
    7. [loopsimplify] Loop simplify is really slow on 252.eon
    +
    +
    -LLVM gained several improvements to its build and installation -infrastructure in this release. There is now -a autoconf/AutoRegen.sh script that you can run to rebuild the -configure script and its associated files -(Bug 105) as well as beta support -for "make install" (Bug 208 and -Bug 220) and RPM package generation -(Bug 203). -Additionally, in this release, the following build problems were fixed: +In this release, the following build problems were fixed:
    +
      -
    1. [build] Makefiles break if C frontend target string has unexpected value
      2. -
    2. [build] hard-wired assumption that shared-library extension is ".so"
      3. -
    3. make tools-only doesn't make lib/Support
      4. +
    4. Minor configure bugs with +-disable/enable-povray and -disable-spec
      5. +
    5. shell scripts output by gccld don't +work if you change PATH
      6. +
    6. [llvmgcc] llvmgcc does not compile +with gcc 3.4
      7. +
    7. [llvmgcc] obstack.h relies on +obsolete casts-as-lvalues GCC extension
    +
    -In this release, the following Code Quality issues were fixed: +This release includes the following Code Quality +improvements:
    +
      -
    1. [loopsimplify] Many pointless phi nodes are created
      2. -
    2. The X86 backend didn't generate fchs to negate floating point numbers
      3. -
    3. The X86 backend didn't expand memcpy() into the rep movs instruction
      4. -
    4. [x86] wierd stack/frame pointer manipulation
      5. -
    +
  10. Fixed: [vmcore] Code quality problem +due to long operand of getelementptr
    11. + +
  11. The X86 backend now generates substantially better code for 64-bit integer +and floating point operations.
    12. + +
  12. The -inline pass no longer inlines mutually recursive functions until it +hits the inlining threshold.
    13. + +
  13. The -inline pass no longer misses obvious inlining opportunities just +because the callee eventually calls into an external function.
    14. + +
  14. The -simplifycfg pass can now "if convert" simple statements into the new +select instruction.
    15. + +
  15. The -loopsimplify pass can now break natural loops with multiple backedges +into multiple nested loops. This enables a variety of subsequent +optimizations.
    16. + +
  16. The -adce pass can now eliminate calls to functions that do not not write to +memory.
    17. + +
  17. The link-time optimizer now runs the -prune-eh pass (to remove unused +exception handlers).
    18. + +
  18. The -simplifycfg pass can now eliminate simple correlated branches (such as +"if (A < B && A < B)", and can turn short-circuiting +operators into the strict versions when useful (such as "if (A < B || A +> C)" into "if (A < B | A > C)"
    19. +
  19. LLVM now has infrastructure for (simple and sparse conditional) constant +propagation of function calls. It currently supports a few math library +functions like sqrt/sin/cos/etc.
    20. + +
  20. The C backend now emits Syntactic +loops in the code to help C compilers whose optimizers do not recognize +loops formed from gotos (like GCC).
    21. + +
  21. Fixed: [sparcv9] null +often spilled to constant pool.
    22. +
+
-In this release, the following bugs in the previous release were fixed: +In this release, the following bugs in the previous release +were fixed:
+
+

Bugs in the LLVM Core:

    -
  1. [licm] LICM promotes volatile memory -locations to registers
    2. -
  2. [licm] Memory read after free causes -infrequent crash
    3. -
  3. [indvars] Induction variable -canonicalization always makes 32-bit indvars
    4. -
  4. [constantmerge] Merging globals can -cause use of invalid pointers!
    5. -
  5. [bcreader] Bytecode reader misreads 'long -9223372036854775808'!
    6. -
  6. Tail duplication does not update SSA form correctly.
    7. -
  7. VMCore mishandles double -0.0
    8. -
  8. [X86] X86 backend code generates -0.0 as +0.0
    9. -
  9. [loopsimplify] Loopsimplify incorrectly updates dominator information
    10. -
  10. [pruneeh] -pruneeh pass removes invoke instructions it shouldn't
    11. -
  11. [sparc] Boolean constants are emitted as true and false
    12. -
  12. Tablegen aborts on errors
    13. -
  13. [inliner] Error inlining intrinsic calls into invoke instructions
    14. -
  14. Linking weak and strong global variables is dependent on link order
    15. +
  15. [loopsimplify] Loop simplify +incorrectly updates dominator information
    16. +
  16. [tailduplicate] DemoteRegToStack +breaks SSA form
    17. +
  17. [X86] JIT miscompiles unsigned short +to floating point cast
    18. +
  18. [jit] abort, don't warn, when +missing external functions encountered
    19. +
  19. [vmcore] Linker causes erroneous +asssertion
    20. +
  20. [adce] Crash handling unreachable +code that unwinds
    21. +
  21. [sparcv9] LLC can't emit 2 functions +of the same name, both having constant pools
    22. +
  22. [livevar] Live variables missed +physical register use of aliased definition
    23. +
  23. Verifier misses malformed switch +instruction
    24. +
  24. [asmwriter] Asm writer aborts if +an instruction is not embedded into a function
    25. +
  25. [X86] stackifier crash on floating +point setcc X, X
- -

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

    -
  1. Need weak linkage on memory -management functions in libc runtime to allow them to be overriden
    2. -
  2. [llvm-gcc] asserts when an extern inline function is redefined
    3. -
  3. [llvmg++] Dynamically initialized constants cannot be marked 'constant'
    4. -
  4. [llvmgcc] floating-point unary minus is incorrect for +0.0
    5. -
  5. [llvm-gcc] miscompilation of 'X = Y = Z' with aggregate values
    6. -
  6. [llvmgcc] Structure copies result in a LOT of code
    7. -
  7. [llvm-gcc] miscompilation when a function is re-declared as static
    8. +
  8. [llvmgcc] Variable length array +indexing miscompiled
    9. +
  9. [llvmgcc] Crash on use of undeclared +enum type
    10. +
  10. [llvmgcc] Errors handling function +prototypes that take opaque structs by-value
    11. +
  11. [llvmgcc] Crash compiling variable +length array of structures
    12. +
  12. [llvmgcc] miscompilation of staticly +initialized unsigned bitfields
    13. +
  13. [llvm-gcc] Crash casting function to void
-
@@ -206,15 +319,46 @@ management functions in libc runtime to allow them to be overriden
-

LLVM has been extensively tested on Intel and AMD machines running Red -Hat Linux and FreeBSD. It has also been tested on Sun UltraSPARC workstations running Solaris 8. -Additionally, -LLVM works on Mac OS X 10.3 and above, but only with the C backend or -interpreter (no native backend for the PowerPC is available yet). -The core LLVM infrastructure uses "autoconf" for portability, so hopefully we -work on more platforms than that. However, it is likely that we -missed something and that minor porting is required to get LLVM to work on -new platforms. We welcome portability patches and error messages.

+

LLVM is known to work in 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.

+ +

Note that the LLVM build system does not currently support directories with +spaces on them when running on Win32/cygwin. We strongly recommend running +LLVM and the C frontend out of a top-level directory without spaces (e.g., +/cygdrive/c/llvm). Also, make sure to install all of the +cygwin packages. By default, many important tools are not installed that +are needed by the LLVM build process or test suite (e.g., /bin/time).

+ +
+ + +
+In this release, the following portability problems were fixed: +
+ +
+ +
    +
  1. warnings compiling Stacker compiler +on Mac OS X
    2. +
  2. Archive file reader doesn't +understand abbreviated names in headers
    3. +
@@ -234,11 +378,30 @@ 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.

+ + +
@@ -261,13 +424,11 @@ corrupted.
  • Linking in static archive files (.a files) is very slow (there is no symbol table in the archive).
    • -
  • LLVM cannot handle structures with -more than 256 elements.
    • - -
  • The gccld program does not link objects/archives in the order specified on the command line.
    • +
  • The gccld program does not link +objects/archives in the order specified on the command line.
  • The lower-invoke pass does not mark -values live across a setjmp as volatile. This missing feature only effects +values live across a setjmp as volatile. This missing feature only affects targets whose setjmp/longjmp libraries do not save and restore the entire register file.
    • @@ -292,11 +453,13 @@ register file. } -
  • -Initialization of global union variables can only be done -with the largest -union member. -
    • +
  • Initialization of global union variables can only be done with the largest union +member.
    • + +
  • [llvm-gcc] Error when an implicitly +external function is re-declared as static
    • +
    @@ -329,7 +492,6 @@ work: the following extensions are known to not be supported:
    1. Local Labels: Labels local to a block.
      2. -
    2. Labels as Values: Getting pointers to labels and computed gotos.
    3. Nested Functions: As in Algol and Pascal, lexical scoping of functions.
    4. Constructing Calls: Dispatching a call to another function.
    5. Extended Asm: Assembler instructions with C expressions as operands.
      6. @@ -393,16 +555,18 @@ work: We support all builtins which have a C language equivalent (e.g., __builtin_cos), __builtin_alloca, __builtin_types_compatible_p, __builtin_choose_expr, - __builtin_constant_p, and __builtin_expect (ignored). - + __builtin_constant_p, and __builtin_expect + (currently ignored). We also support builtins for ISO C99 floating + point comparison macros (e.g., __builtin_islessequal).

    The following extensions are known to be supported:

      +
    1. Labels as Values: Getting pointers to labels and computed gotos.
    2. Statement Exprs: Putting statements and declarations inside expressions.
    3. Typeof: typeof: referring to the type of an expression.
      4. -
    4. Lvalues: Using ?:, "," and casts in lvalues.
      5. +
    5. Lvalues: Using ?:, "," and casts in lvalues.
    6. Conditionals: Omitting the middle operand of a ?: expression.
    7. Long Long: Double-word integers.
    8. Complex: Data types for complex numbers.
      9. @@ -509,20 +673,27 @@ href="http://gcc.gnu.org/gcc-3.4/changes.html">GCC 3.4 release notes.
      - Known problems with the Sparc back-end + Known problems with the SparcV9 back-end