Don't need to compile undefineds.c on sparc.
Fix error in computation (log number base) where one of the args is a
double-double.

 * src/code/irrat.lisp:
   * For the following two cases, cmucl generated an error instead of
     computing the log
     * Base is a double-double but number is not.
     * Number is a double-double but base is not.
 * tests/irrat.lisp:
   * Add some tests for log2 and log10.
Regenerate.
Add tests for log2 and log10.
Fix bug in dd-%log2 where (dd-%log2 100w0) returned 6.16 instead of
6.64.

Tests were already added to tests/irrat.lisp.
Add log10 implementation for double-doubles.

Since log2 and log10 use basically the same natural log
implementation, factor that out the common part into its own routine.
Return -infinity for %log2 and %log10 of +0.
Use log2 and log10 functions when possible instead of using the
general case.
 * Add tests for dd-%log2 and dd-%log10.
 * Fix the log10.result-types test because we return correctly rounded
   results for these few tests.
Extract the log2 code out of e_pow.c to implement log2 function.

 * log2.c:
   * New file containing the parts of e_pow.c that implemented a log2
     function for use in pow().
 * GNUmakefile:
   * Compile log2.c as part of the build.
Use new log2 function in C

 * code/exports.lisp:
   * Export %LOG2.
 * code/irrat.lisp:
   * Define %log2
   * Use %log2 instead of log2. (This needs work)
 * compiler/float-tran.lisp:
   * Use %log2 instead of log2 in the deftransforms.
Fix some issues with log2 and log10 of big rationals.

 * src/code/irrat.lisp:
   * Add log10 function to handle the computation of the base 10 log
     of big rationals that might not fit in a double-float.
   * Fix some issues where CL:LOG wasn't handling logs of big
     rationals. (A regression).
 * tests/trac.lisp:
   * Update trac.8 test to include logs base 10.
Fix up a few more issues with log.

 * src/code/irrat.lisp:
   * In log10, return the correct type for the result.  Previously, we
     would return a double even if a single were desired.
   * Fix up a few more cases where we failed to handle log of a huge
     rational correctly for log base 2 and base 10.
 * tests/irrat.lisp:
   * Add some tests to check that log returns the correct type of
     number for the log base 2 and 10 of very large rationals.
Correct the tests for the generic function lambda lists.

The check for invalid gf lambda lists happens during macroexpansion,
so update the tests to catch this during macroexpansion.

This fixes three of the issues in ticket:95.
Signal an error for an invalid :allocation value for a slot.

Fixes ticket:95, along with changeset:[2b39eb]
Add function to print a description of the value of the FPSCR
(floating-point status and control register).
Partially addresses ticket:91 by allowing the test suite to finish.
The tests still fail (along with others), but the test suite will
finish.

 * code/float-trap.lisp:
   * Update SET-FLOATING-POINT-MODES:
     * When we clear out bits in float-invalid-op-1-byte, clear out the
       float-invalid-op-2-byte.  Not necessary for this fix, but those
       bits signal other invalid operations from sqrt and such.
     * When clearing the exceptions, clear the sticky exceptions
       summary bit too.
   * Fix SIGFPE-HANDLER:
     * As above, clear out the bit in float-invalid-op-2-byte and the
       exceptions summary bit.
     * Only clear out the new exception bits, as done for SSE2.
     * Mask out the float-invalid-op-2-byte and the summary bit before
       setting the new modes.

 * compiler/ppc/parms.lisp
   * Define float-exceptions-summary-byte.

 * code/exports.lisp:
   * Export FLOAT-INVALID-OP-2-BYTE
See ticket:91: Forgot to export FLOAT-EXCEPTIONS-SUMMARY-BYTE.
Fix to handle (log 3/2 2) and (log -3/2 2).  Test added.

 * src/code/irrat.lisp:
   * Fix LOG2 to handle the case of negative rational numbers.
   * Fix LOG of rational to a rational base. We want to convert the
     log of the number to a single float because log2 isn't intended
     to handle single-float type.

 * tests/irrat.lisp:
   * Add test for log of rational to rational base.
   * Add some additional tests for dd-%log2.
Don't bother to build clm or motifd on darwin/ppc. It's not likely
we'll ever install motif on that machine.