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Release 1.6, 2010-01-13
=======================

- Support Clight initializers of the form "int * x = &y;".

- Fixed spurious compile-time error on Clight initializers of the form
  "const enum E x[2] = { E_1, E_2 };".

- Produce informative error message if a 'return' without argument
  occurs in a non-void function, or if a 'return' with an argument
  occurs in a void function.

- Preliminary support for '#pragma section' and '#pragma set_section'.

- Preliminary support for small data areas in PowerPC code generator.

- Back-end: added support for jump tables; used them to compile
  dense 'switch' statements.

- PowerPC code generator: force conversion to single precision before
  doing a "store single float" instruction.


Release 1.5, 2009-08-28
=======================

- Support for "goto" in the source language Clight.

- Added small-step semantics for Clight.

- Traces for diverging executions are now uniquely defined;
  tightened semantic preservation results accordingly.

- Emulated assignments between structures 
  (during the C to Clight initial translation).

- Fixed spurious compile-time error on Clight statements of the form
  "x = f(...);" where x is a global variable.

- Fixed spurious compile-time error on Clight initializers where
  the initial value is the result of a floating-point computation
  (e.g. "double x = 3.14159 / 2;").

- Simplified the interface of the generic dataflow solver.

- Reduced running time and memory requirements for the constant propagation
  pass.

- Improved the implementation of George and Appel's graph coloring heuristic:
  runs faster, produces better results.

- Revised the implementation of branch tunneling.

- Improved modularization between processor-dependent and
  processor-independent parts.


Release 1.4.1, 2009-06-05
=========================

- Adapted to Coq 8.2-1.  No changes in functionality.

Release 1.4, 2009-04-20
=======================

- Modularized the processor dependencies in the back-end.

- Three target architectures are now supported:
       PowerPC / MacOS X       (most mature)
       PowerPC / EABI & Linux  (getting stable)
       ARM / Linux EABI        (still experimental)

- Added alignment constraints to the memory model.

- Clight: added support for conditional expressions (a ? b : c);
  removed support for array accesses a[i], now a derived form.

- C front-end: honor "static" modifiers on globals.

- New optimization over RTL: turning calls into tail calls when possible.

- Instruction selection pass: elimination of redundant casts following
  a memory load of a "small" memory quantity.

- Linearization pass: improved the linearization heuristic.

- Reloading pass: more economical use of temporaries.

- Back-end: removed "alloc heap" instruction; removed pointer validity
  checks in pointer comparisons.


Release 1.3, 2008-08-11
=======================

- Added "goto" and labeled statements to Cminor.  Extended RTLgen and
    its proof accordingly.

- Introduced small-step transition semantics for Cminor; used it in
    proof of RTLgen pass; proved consistency of Cminor big-step semantics
    w.r.t. transition semantics.

- Revised division of labor between the Allocation pass and the Reload pass.
    The semantics of LTL and LTLin no longer need to anticipate the passing
    of arguments through the conventional locations.

- Cleaned up Stacking pass: the positions of the back link and of
    the return address in the stack frame are no longer hard-wired
    in the Mach semantics.

- Added operator to convert from float to unsigned int; used it in C front-end

- Added flag -fmadd to control recognition of fused multiply-add and -sub

- Semantics of pointer-pointer comparison in Clight was incomplete:
    pointers within different blocks can now be compared using == or !=

- Addition integer + pointer is now supported in Clight.

- Improved instruction selection for complex conditions involving || and &&.

- Improved translation of Cminor "switch" statements to RTL decision trees.

- Fixed error in C parser and simplifier related to "for" loops with
    complex expressions as condition.

- More benchmark programs in test/



Release 1.2, 2008-04-03
=======================

- First public release