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authorlemon <lsof@mailbox.org>2025-10-19 08:09:09 +0200
committerlemon <lsof@mailbox.org>2025-10-19 08:09:09 +0200
commitdea8fd171acb54b6d9685422d5e391fb55074008 (patch)
tree2c149892f35c5183c9b2a1da4ab437228dc432ef /optmem.c
parent3437945692f2b87883a4f066473c9deed50f25f5 (diff)
Organize source files into directories
Diffstat (limited to 'optmem.c')
-rw-r--r--optmem.c285
1 files changed, 0 insertions, 285 deletions
diff --git a/optmem.c b/optmem.c
deleted file mode 100644
index 1c137b7..0000000
--- a/optmem.c
+++ /dev/null
@@ -1,285 +0,0 @@
-#include "ir.h"
-
-static const uchar loadszcls[] = {
- [Oloads1 - Oloads1] = 1|KI4<<4, [Oloadu1 - Oloads1] = 1|KI4<<4,
- [Oloads2 - Oloads1] = 2|KI4<<4, [Oloadu2 - Oloads1] = 2|KI4<<4,
- [Oloads4 - Oloads1] = 4|KI4<<4, [Oloadu4 - Oloads1] = 4|KI4<<4,
- [Oloadi8 - Oloads1] = 8|KI8<<4,
- [Oloadf4 - Oloads1] = 4|KF4<<4,
- [Oloadf8 - Oloads1] = 8|KF8<<4,
-};
-static const uchar load2ext[] = {
- [Oloads1 - Oloads1] = Oexts1, [Oloadu1 - Oloads1] = Oextu1,
- [Oloads2 - Oloads1] = Oexts2, [Oloadu2 - Oloads1] = Oextu2,
- [Oloads4 - Oloads1] = Oexts4, [Oloadu4 - Oloads1] = Oextu4,
- [Oloadi8 - Oloads1] = Ocopy,
-};
-#define loadsz(o) (loadszcls[(o) - Oloads1] & 0xF)
-#define loadcls(o) (loadszcls[(o) - Oloads1] >> 4)
-#define load2ext(o) (load2ext[(o) - Oloads1])
-#define storesz(o) (1 << ((o) - Ostore1))
-
-/* Implements algorithm in 'Simple and Efficient Construction of Static Single Assignment' (Braun et al) */
-
-struct pendingphi { ushort var, phi; };
-struct ssabuilder {
- vec_of(struct pendingphi) *pendingphis; /* map of block to list of incomplete phis in block */
- imap_of(union ref *) curdefs; /* map of var to (map of block to def of var) */
- struct bitset *sealed;
- int lastvisit;
- int nblk;
-};
-
-static union ref readvar(struct ssabuilder *, int var, enum irclass, struct block *);
-
-static union ref
-deltrivialphis(struct ssabuilder *sb, struct block *blk, union ref phiref)
-{
- union ref **pcurdefs;
- int var;
- struct use *use, *uend;
- union ref *args = phitab.p[instrtab[phiref.i].l.i];
- union ref same = {0};
-
- assert(instrtab[phiref.i].op == Ophi);
-
- for (int i = 0; i < blk->npred; ++i) {
- if (args[i].bits == same.bits || args[i].bits == phiref.bits) {
- continue; /* unique value or self-reference */
- } if (same.bits != 0) {
- return phiref; /* non-trivial */
- }
- same = args[i];
- }
-
- if (same.bits == 0)
- same = UNDREF; /* the phi is unreachable or in the start block */
-
- /* replace uses */
- replcuses(phiref, same);
- imap_each(&sb->curdefs, var, pcurdefs) {
- (void)var;
- for (int i = blk->id; i < sb->nblk; ++i) {
- if ((*pcurdefs)[i].bits == phiref.bits)
- (*pcurdefs)[i] = same;
- }
- }
-
- /* stops infinite recursion and marks phi for removal */
- instrtab[phiref.i].op = Onop;
-
- /* recursively try to remove all phi users as they might have become trivial */
-Redo:
- for (use = instruse[phiref.i], uend = use + instrnuse[phiref.i]; use < uend; ++use) {
- if (use->u != USERJUMP && instrtab[use->u].op == Ophi && use->u != phiref.i) {
- union ref it = mkref(RTMP, use->u);
- union ref vphi2 = deltrivialphis(sb, use->blk, it);
- if (vphi2.bits != it.bits) {
- /* deletion happened so phiref use may have changed */
- if (same.bits == it.bits) same.bits = vphi2.bits;
- goto Redo;
- }
- }
- }
- deluses(phiref.i);
-
- return same;
-}
-
-static union ref
-addphiargs(struct ssabuilder *sb, int var, enum irclass cls, struct block *blk, union ref phiref)
-{
- union ref *args = phitab.p[instrtab[phiref.i].l.i];
- for (int i = 0; i < blk->npred; ++i) {
- struct block *pred = blkpred(blk, i);
- args[i] = readvar(sb, var, cls, pred);
- adduse(blk, phiref.i, args[i]);
- }
- return deltrivialphis(sb, blk, phiref);
-}
-
-static void
-writevar(struct ssabuilder *sb, int var, struct block *blk, union ref val)
-{
- union ref **pcurdefs;
- if (!(pcurdefs = imap_get(&sb->curdefs, var))) {
- pcurdefs = imap_set(&sb->curdefs, var, xcalloc(sb->nblk * sizeof(union ref)));
- }
- if (val.t == RTMP) assert(instrtab[val.i].op != Onop);
- (*pcurdefs)[blk->id] = val;
-}
-
-static union ref
-readvarrec(struct ssabuilder *sb, int var, enum irclass cls, struct block *blk)
-{
- union ref val;
- assert(blk->npred > 0);
- if (!bstest(sb->sealed, blk->id)) { /* unsealed block */
- val = insertphi(blk, cls);
- vpush(&sb->pendingphis[blk->id], ((struct pendingphi) { var, val.i }));
- } else if (blk->npred == 1) {
- val = readvar(sb, var, cls, blkpred(blk, 0));
- } else {
- val = insertphi(blk, cls);
- writevar(sb, var, blk, val);
- val = addphiargs(sb, var, cls, blk, val);
- }
- writevar(sb, var, blk, val);
- return val;
-}
-
-static union ref
-readvar(struct ssabuilder *sb, int var, enum irclass cls, struct block *blk)
-{
- union ref **pcurdefs;
- if ((pcurdefs = imap_get(&sb->curdefs, var)) && (*pcurdefs)[blk->id].bits)
- return (*pcurdefs)[blk->id];
- if (blk->npred == 0) /* entry block, var is read before being written to */
- return UNDREF;
- return readvarrec(sb, var, cls, blk);
-}
-
-static bool
-trysealrec(struct ssabuilder *sb, struct block *blk)
-{
- vec_of(struct pendingphi) *pending;
-
-Recur:
- if (bstest(sb->sealed, blk->id)) return 1;
- if (blk->id > sb->lastvisit) return 0;
- markvisited(blk);
- for (int i = 0; i < blk->npred; ++i) {
- struct block *p = blkpred(blk, i);
- if (wasvisited(p)) continue;
- if (!trysealrec(sb, p)) return 0;
- }
-
- bsset(sb->sealed, blk->id);
- pending = (void *) &sb->pendingphis[blk->id];
- for (int i = 0; i < pending->n; ++i) {
- addphiargs(sb, pending->p[i].var, instrtab[pending->p[i].phi].cls, blk,
- mkref(RTMP, pending->p[i].phi));
- }
- vfree(pending);
- if (blk->s1 && !blk->s2) {
- blk = blk->s1;
- goto Recur;
- } else if (blk->s1 && blk->s2) {
- trysealrec(sb, blk->s1);
- blk = blk->s2;
- goto Recur;
- }
- return 1;
-}
-
-static void
-tryseal(struct ssabuilder *sb, struct block *blk)
-{
- startbbvisit();
- trysealrec(sb, blk);
-}
-
-/* require use, blkid; keeps use */
-void
-mem2reg(struct function *fn)
-{
- static struct bitset ssealed[4];
- struct ssabuilder sb = { .nblk = fn->nblk };
- struct block *blk;
-
- sb.pendingphis = xcalloc(fn->nblk * sizeof *sb.pendingphis);
- if (fn->nblk <= 64 * arraylength(ssealed)) {
- sb.sealed = ssealed;
- memset(ssealed, 0, BSSIZE(fn->nblk) * sizeof *ssealed);
- } else {
- sb.sealed = xcalloc(BSSIZE(fn->nblk) * sizeof *sb.sealed);
- }
-
- sortrpo(fn);
- blk = fn->entry;
-
- do {
- for (int i = 0; i < blk->ins.n; ++i) {
- struct use *use, *uend;
- enum irclass k = 0;
- int sz = 0, ndef = 0;
- enum op ext = Ocopy;
- int var = blk->ins.p[i];
- struct instr *ins = &instrtab[var];
-
- if (!oisalloca(ins->op)) continue;
- uend = instruse[var] + instrnuse[var];
- for (use = instruse[var]; use < uend; ++use) {
- struct instr *m;
-
- if (use->u == USERJUMP) goto Next;
- m = &instrtab[use->u];
- if (oisload(m->op) && (!sz || sz == loadsz(m->op))) {
- sz = loadsz(m->op);
- k = loadcls(m->op);
- if (sz < 4) ext = load2ext(m->op);
- continue;
- }
- if (oisstore(m->op) && m->l.bits == mkref(RTMP, var).bits
- && (!sz || sz == storesz(m->op))) {
- sz = storesz(m->op);
- ++ndef;
- continue;
- }
- goto Next;
- }
- if (!ndef) /* slot is read from but never written to */
- goto Next;
-
- for (use = instruse[var]; use < uend; ++use) {
- struct instr *m = &instrtab[use->u];
-
- if (oisstore(m->op)) {
- writevar(&sb, var, use->blk, m->r);
- *m = mkinstr(Onop,0,);
- } else if (oisload(m->op)) {
- union ref val = readvar(&sb, var, k = m->cls, use->blk);
- if (!val.bits) { /* var is used uninitialized */
- /* TODO emit diagnostic */
- /* load some garbage */
- *m = mkinstr(kisflt(k) ? Oloadf4 + (k==KF8) : Oloads1+ilog2(sz)*2,
- k, mkref(RREG, mctarg->bpr));
- } else {
- adduse(use->blk, use->u, val);
- *m = mkinstr(ext, k, val);
- }
- }
- }
- /* remove alloca */
- delinstr(blk, i--);
-
- Next:;
- }
-
- assert(sb.lastvisit == blk->id);
- ++sb.lastvisit;
- tryseal(&sb, blk);
- } while ((blk = blk->lnext) != fn->entry);
-
- do {
- /* remove phis marked for deletion */
- for (int i = 0; i < blk->phi.n; ++i)
- if (instrtab[blk->phi.p[i]].op == Onop)
- delphi(blk, i--);
- } while ((blk = blk->lnext) != fn->entry);
-
- if (sb.sealed != ssealed) free(sb.sealed);
- free(sb.pendingphis);
-
- for (int i = 0; i < sb.curdefs.mb.N; ++i)
- if (bstest(sb.curdefs.mb.bs, i))
- free(sb.curdefs.v[i]);
- imap_free(&sb.curdefs);
- if (ccopt.dbg.m) {
- efmt("<< After mem2reg >>\n");
- irdump(fn);
- }
-}
-
-
-/* vim:set ts=3 sw=3 expandtab: */