From b4a98c3fa8b880f58b04f5d632ab89ad15725bd4 Mon Sep 17 00:00:00 2001 From: Quentin Carbonneaux Date: Thu, 25 Apr 2019 15:27:25 +0200 Subject: cleanup amd64 constant addressing We now emit correct code when the user refers to a specific constant address. I also made some comments clearer in the instruction selection pass and got rid of some apparently useless code. --- amd64/emit.c | 12 +++++++----- amd64/isel.c | 30 ++++++++++++------------------ 2 files changed, 19 insertions(+), 23 deletions(-) (limited to 'amd64') diff --git a/amd64/emit.c b/amd64/emit.c index 1fe141f..91223bd 100644 --- a/amd64/emit.c +++ b/amd64/emit.c @@ -292,10 +292,10 @@ Next: if (m->offset.type != CUndef) emitcon(&m->offset, f); fputc('(', f); - if (req(m->base, R)) - fprintf(f, "%%rip"); - else + if (!req(m->base, R)) fprintf(f, "%%%s", regtoa(m->base.val, SLong)); + else if (m->offset.type == CAddr) + fprintf(f, "%%rip"); if (!req(m->index, R)) fprintf(f, ", %%%s, %d", regtoa(m->index.val, SLong), @@ -333,8 +333,10 @@ Next: fprintf(f, "%d(%%rbp)", slot(ref.val, fn)); break; case RCon: - emitcon(&fn->con[ref.val], f); - fprintf(f, "(%%rip)"); + off = fn->con[ref.val]; + emitcon(&off, f); + if (off.type == CAddr) + fprintf(f, "(%%rip)"); break; case RTmp: assert(isreg(ref)); diff --git a/amd64/isel.c b/amd64/isel.c index cedfdb1..ce0c98f 100644 --- a/amd64/isel.c +++ b/amd64/isel.c @@ -62,7 +62,7 @@ static void fixarg(Ref *r, int k, int op, Fn *fn) { char buf[32]; - Addr a, *m; + Addr a; Ref r0, r1; int s, n, cpy, mem; @@ -103,23 +103,13 @@ fixarg(Ref *r, int k, int op, Fn *fn) } else if (!mem && rtype(r0) == RCon && fn->con[r0.val].type == CAddr) { - /* apple asm fix */ + /* apple as does not support 32-bit + * absolute addressing, use a rip- + * relative leaq instead + */ r1 = newtmp("isel", Kl, fn); emit(Oaddr, Kl, r1, r0, R); } - else if (rtype(r0) == RMem) { - /* apple asm fix */ - m = &fn->mem[r0.val]; - if (req(m->base, R)) { - n = fn->ncon; - vgrow(&fn->con, ++fn->ncon); - fn->con[n] = m->offset; - m->offset.type = CUndef; - r0 = newtmp("isel", Kl, fn); - emit(Oaddr, Kl, r0, CON(n), R); - m->base = r0; - } - } *r = r1; } @@ -134,9 +124,13 @@ seladdr(Ref *r, ANum *an, Fn *fn) memset(&a, 0, sizeof a); if (!amatch(&a, r0, an[r0.val].n, an, fn)) return; - if (a.offset.type == CAddr) - if (!req(a.base, R)) { - /* apple asm fix */ + if (!req(a.base, R)) + if (a.offset.type == CAddr) { + /* apple as does not support + * $foo(%r0, %r1, M); try to + * rewrite it or bail out if + * impossible + */ if (!req(a.index, R)) return; else { -- cgit 1.4.1