Teach stack promotion to walk the CFG when a potential reuse of an allocation is found to see if it can actually happen instead of just assuming it will. This allows it to catch cases like {{{ int i; Foo f; while (cond(i)) f = new Foo(i++); return f.value; }}} where it previously wouldn't because a phi using the allocation would appear in the condition block to propagate it to the use after the loop.

#!/bin/bash

HOST_TARGET=$1

[ "$HOST_TARGET" = "" ] && exit 1

REST=`echo $HOST_TARGET   | sed -e 's/[a-zA-Z0-9_]*\(\-.*\)/\1/'`
X86=`echo $HOST_TARGET    | sed -e 's/\(i[3-9]86\)\-.*/\1/'`
X86_64=`echo $HOST_TARGET | sed -e 's/\(x86_64\)\-.*/\1/'`

ALT=
if [ "$X86_64" != "$HOST_TARGET" ]; then
    ALT="i686$REST"

elif [ "$X86" != "$HOST_TARGET" ]; then
    ALT="x86_64$REST"
fi

echo $ALT