🚀 go-pugleaf

Gcc 1.34 does not reuse space on stack that was used by
variable local to the block that has ended.

Variables k and kk in the bl.c could exist in the same place
on stack, but gcc allocates separate words for each of them.
Although not wrong, this is wasteful. 

Sun cc reuses that space.

======================================================================
Script started on Thu Mar 30 14:24:52 1989
!21 mars:c -> cat bl.c


void f (j)
  int j;
{
  int i;
  {
    int k;

    i = k+j;
  }
  {
    int kk;

    i = kk+j;
  }
}
!22 mars:c -> gcc -ansi -pedantic -Wall -Wwrite-strings -v -S bl.c
gcc version 1.34
 /usr/local/lib/gcc-cpp -v -undef -D__GNUC__ -T -$ -D__STRICT_ANSI__ -D__mc68000__ -D__sun__ -D__unix__ -pedantic -Wall -D__HAVE_68881__ bl.c /tmp/cca26952.cpp
GNU CPP version 1.34
 /usr/local/lib/gcc-cc1 /tmp/cca26952.cpp -quiet -dumpbase bl.c -Wall -Wwrite-strings -pedantic -ansi -version -o bl.s
GNU C version 1.34 (68k, MIT syntax) compiled by GNU C version 1.34.
!23 mars:c -> cat bl.s
#NO_APP
gcc_compiled.:
.text
        .even
.globl _f
_f:
        link a6,#-12
        movel a6@(-8),d0  # int k
        addl a6@(8),d0
        movel d0,a6@(-4)
        movel a6@(-12),d0  # int kk
        addl a6@(8),d0
        movel d0,a6@(-4)
L1:
        unlk a6
        rts
!24 mars:c -> exit

script done on Thu Mar 30 14:25:34 1989
======================================================================

Drazen Borkovic, Caltech 256-80, Pasadena, CA 91125      
e-mail: drazen@vlsi.caltech.edu