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Thu Aug 29 20:40:51 2019 UTC (5 months, 3 weeks ago) by maya
Branches: MAIN
CVS tags: HEAD
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# Various GCC/vax issues and invesigation #

## libgomp crash with -O2 ##
Repro:

    #!/bin/sh
    
    cat << EOF > oacc.i
    int a, b;
    int e() {
      short *c = 0;
      char d = c[a + 1];
      b = d;
      a += 2;
    }
    EOF
    vax--netbsdelf-gcc -O2 -c oacc.i

Asserts at emit-rtl.c:2310 gcc_assert (memory_address_addr_space_p (mode, addr, as));

NetBSD avoids it with a [local diff](5f534f20bc66738c05c442a8f20088f55335b653/external/gpl3/gcc/dist/libgcc/gthr-posix.h#L418) to reload.c/dse.c.  
It looks like a real bug in vax_legitimate_address_p not handling some addressing modes.  
The code to handle offset(reg)[index] might be off: it doesn't like if neither xfoo0, xfoo1 are constant.

## unrecognizable insn with any optimization ##

Repro:

    #!/bin/sh

    cat << EOF > decl.ii
    struct a {
      long long *b() const;
    };
    template <typename> class d : a {
    public:
      template <typename e> d(e);
      long long f() const;
    };
    template <typename c> long long d<c>::f() const {
      int g;
      return b()[g];
    }
    int h;
    bool i() {
      d<int> j(h);
      return j.f();
    }
    EOF
    vax--netbsdelf-g++ -O2 -c decl.ii


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