PPL: Remove support for PPL and CLooG/PPL

Now that versions of gcc that required PPL are no longer supported
( >= gcc-4.5.x AND <= gcc-4.7.x )
...we no longer require PPL or CLooG/PPL.

This commit:

* Removes PPL
* Removes CLooG/PPL
* Updates the documentation
* Updates build script for CLooG and GCC
* Removes PPL and CLooG/PPL from scripts/addToolVersion.sh and
  scripts/showSamples.sh
* Adds ISL to scripts/addToolVersion.sh and scripts/showSamples.sh

I know that sounds like a lot for one commit, but it was all kind of
inter-tangled.

Signed-off-by: Bryan Hundven <bryanhundven@gmail.com>

config/cc/gcc.in

@@ -156,7 +156,8 @@ config CC_GCC_latest
 config CC_GCC_HAS_GRAPHITE
     bool
 
-# For graphite: gcc 4.4..4.7 need ppl, while 4.8.. need isl
+# For graphite: gcc needs cloog and isl
+# In >= gcc-5.x, cloog is no longer needed, but isl is.
 # Prompt in config/cc/gcc.in.2
 config CC_GCC_USE_GRAPHITE
     bool
@@ -167,10 +168,12 @@ config CC_GCC_USE_GRAPHITE
     help
       Enable the GRAPHITE loop optimsations.
 
-      On some systems (eg. Cygwin), PPL and/or CLooG (required to enable
+      On some systems (eg. Cygwin), CLooG and ISL (required to enable
       GRAPHITE) may not build properly (yet), so you'll have to say 'N'
       here (or help debug the issues)
 
+      TODO: Is this still true on Cygwin?
+
 # The way LTO works is a bit twisted.
 # See: http://gcc.gnu.org/wiki/LinkTimeOptimization#Requirements
 # Basically:

config/cc/gcc.in.2

@@ -68,7 +68,7 @@ config CC_GCC_STATIC_LIBSTDCXX
     default y
     select WANTS_STATIC_LINK
     help
-      Newer gcc versions use the PPL library which is C++ code.  Statically
+      Newer gcc versions require some c++ libraries. So statically
       linking libstdc++ increases the likeliness that the gcc binary will
       run on machines other than the one which it was built on, without
       having to worry about distributing the matching version of libstdc++

config/companion_libs.in

@@ -28,11 +28,6 @@ config MPFR_NEEDED
     select MPFR
     select COMPLIBS_NEEDED
 
-config PPL_NEEDED
-    bool
-    select PPL
-    select COMPLIBS_NEEDED
-
 config ISL_NEEDED
     bool
     select ISL
@@ -83,11 +78,6 @@ config MPFR
     select GMP
     select COMPLIBS
 
-config PPL
-    bool
-    select GMP
-    select COMPLIBS
-
 config ISL
     bool
     select GMP
@@ -137,9 +127,6 @@ endif
 if MPFR
 source "config/companion_libs/mpfr.in"
 endif
-if PPL
-source "config/companion_libs/ppl.in"
-endif
 if ISL
 source "config/companion_libs/isl.in"
 endif
@@ -182,9 +169,7 @@ config COMPLIBS_CHECK
 
       If you suspect that one (or more) of your companion libraries is the
       cause for incorrectly generated code, you should answer 'Y' here.
-      Note however that this will take a really long time. For example,
-      building PPL on my machine takes roughly 1'40", while checking it takes
-      about 1h40'...
+      Note however that this will take a really long time.
 
 endif # COMPLIBS
 

config/companion_libs/cloog.in

@@ -26,15 +26,6 @@ config CLOOG_V_0_18_0
 
 endif # ISL
 
-if PPL
-
-config CLOOG_V_0_15_11
-    bool
-    prompt "0.15.11"
-    select CLOOG_NEEDS_AUTORECONF
-
-endif # PPL
-
 endchoice
 
 config CLOOG_VERSION
@@ -44,7 +35,6 @@ config CLOOG_VERSION
     default "0.18.4" if CLOOG_V_0_18_4
     default "0.18.1" if CLOOG_V_0_18_1
     default "0.18.0" if CLOOG_V_0_18_0
-    default "0.15.11" if CLOOG_V_0_15_11
 
 config CLOOG_0_18_4_or_later
     bool

docs/4 - Building the toolchain.txt

@@ -94,7 +94,10 @@ Unfortunately, not all systems on which crosstool-NG runs have all of those
 libraries. And for those that do, the versions of those libraries may be
 older than the version required by gcc (and binutils and gdb). To date,
 Debian stable (aka Lenny) is lagging behind on some, and is missing the
-others.
+others. With >= gcc-4.8, we drop PPL and CLooG/PPL, and switch to ISL to
+replace PPL, and use the upstream version of CLooG instead of CLooG/PPL
+which was a fork of CLooG that provided PPL backend support, that was under-
+maintained. See: https://gcc.gnu.org/wiki/Graphite-4.8
 
 This is why crosstool-NG builds its own set of libraries as part of the
 toolchain.

docs/7 - Contributing to crosstool-NG.txt

@@ -35,7 +35,7 @@ Here is the (mostly-complete) list of categories and components:
     libc        | uClibc, glibc, newlib, mingw, none
     kernel      | linux, mingw32, bare-metal
     debug       | dmalloc, duma, gdb, ltrace, strace
-    complibs    | gmp, mpfr, ppl, cloog, mpc, libelf
+    complibs    | gmp, mpfr, isl, cloog, mpc, libelf
     comptools   | make, m4, autoconf, automake, libtool
     ------------+-------------------------------------------------------
                 | The following categories have no component-part:

docs/9 - How is a toolchain constructed.txt

@@ -199,25 +199,25 @@ loop optimisation (GRAPHITE) and Link Time Optimisation (LTO). If you want
 to use these, you'll need three additional libraries:
 
 To enable GRAPHITE:
-  - the Parma Polyhedra Library, PPL
-  - the Chunky Loop Generator, using the PPL backend, CLooG/PPL
+  - the Interger Set Library, ISL
+  - the Chunky Loop Generator, CLooG
 
 To enable LTO:
   - the ELF object file access library, libelf
 
 The dependencies for those libraries are:
 
-  - PPL requires GMP
-  - CLooG/PPL requires GMP and PPL
+  - ISL requires GMP
+  - CLooG requires GMP and ISL
   - libelf has no pre-requisites
 
 The list now looks like (optional libs with a *):
 
   1 GMP
   2 MPFR
   3 MPC
-  4 PPL *
-  5 CLooG/PPL *
+  4 ISL *
+  5 CLooG *
   6 libelf *
   7 binutils
   8 core pass 1 compiler