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Diffstat (limited to 'libs/luajit-cmake/luajit/src/host/buildvm_fold.c')
-rw-r--r--libs/luajit-cmake/luajit/src/host/buildvm_fold.c236
1 files changed, 236 insertions, 0 deletions
diff --git a/libs/luajit-cmake/luajit/src/host/buildvm_fold.c b/libs/luajit-cmake/luajit/src/host/buildvm_fold.c
new file mode 100644
index 0000000..edb5576
--- /dev/null
+++ b/libs/luajit-cmake/luajit/src/host/buildvm_fold.c
@@ -0,0 +1,236 @@
+/*
+** LuaJIT VM builder: IR folding hash table generator.
+** Copyright (C) 2005-2022 Mike Pall. See Copyright Notice in luajit.h
+*/
+
+#include "buildvm.h"
+#include "lj_obj.h"
+#if LJ_HASJIT
+#include "lj_ir.h"
+
+/* Context for the folding hash table generator. */
+static int lineno;
+static uint32_t funcidx;
+static uint32_t foldkeys[BUILD_MAX_FOLD];
+static uint32_t nkeys;
+
+/* Try to fill the hash table with keys using the hash parameters. */
+static int tryhash(uint32_t *htab, uint32_t sz, uint32_t r, int dorol)
+{
+ uint32_t i;
+ if (dorol && ((r & 31) == 0 || (r>>5) == 0))
+ return 0; /* Avoid zero rotates. */
+ memset(htab, 0xff, (sz+1)*sizeof(uint32_t));
+ for (i = 0; i < nkeys; i++) {
+ uint32_t key = foldkeys[i];
+ uint32_t k = key & 0xffffff;
+ uint32_t h = (dorol ? lj_rol(lj_rol(k, r>>5) - k, r&31) :
+ (((k << (r>>5)) - k) << (r&31))) % sz;
+ if (htab[h] != 0xffffffff) { /* Collision on primary slot. */
+ if (htab[h+1] != 0xffffffff) { /* Collision on secondary slot. */
+ /* Try to move the colliding key, if possible. */
+ if (h < sz-1 && htab[h+2] == 0xffffffff) {
+ uint32_t k2 = htab[h+1] & 0xffffff;
+ uint32_t h2 = (dorol ? lj_rol(lj_rol(k2, r>>5) - k2, r&31) :
+ (((k2 << (r>>5)) - k2) << (r&31))) % sz;
+ if (h2 != h+1) return 0; /* Cannot resolve collision. */
+ htab[h+2] = htab[h+1]; /* Move colliding key to secondary slot. */
+ } else {
+ return 0; /* Collision. */
+ }
+ }
+ htab[h+1] = key;
+ } else {
+ htab[h] = key;
+ }
+ }
+ return 1; /* Success, all keys could be stored. */
+}
+
+/* Print the generated hash table. */
+static void printhash(BuildCtx *ctx, uint32_t *htab, uint32_t sz)
+{
+ uint32_t i;
+ fprintf(ctx->fp, "static const uint32_t fold_hash[%d] = {\n0x%08x",
+ sz+1, htab[0]);
+ for (i = 1; i < sz+1; i++)
+ fprintf(ctx->fp, ",\n0x%08x", htab[i]);
+ fprintf(ctx->fp, "\n};\n\n");
+}
+
+/* Exhaustive search for the shortest semi-perfect hash table. */
+static void makehash(BuildCtx *ctx)
+{
+ uint32_t htab[BUILD_MAX_FOLD*2+1];
+ uint32_t sz, r;
+ /* Search for the smallest hash table with an odd size. */
+ for (sz = (nkeys|1); sz < BUILD_MAX_FOLD*2; sz += 2) {
+ /* First try all shift hash combinations. */
+ for (r = 0; r < 32*32; r++) {
+ if (tryhash(htab, sz, r, 0)) {
+ printhash(ctx, htab, sz);
+ fprintf(ctx->fp,
+ "#define fold_hashkey(k)\t(((((k)<<%u)-(k))<<%u)%%%u)\n\n",
+ r>>5, r&31, sz);
+ return;
+ }
+ }
+ /* Then try all rotate hash combinations. */
+ for (r = 0; r < 32*32; r++) {
+ if (tryhash(htab, sz, r, 1)) {
+ printhash(ctx, htab, sz);
+ fprintf(ctx->fp,
+ "#define fold_hashkey(k)\t(lj_rol(lj_rol((k),%u)-(k),%u)%%%u)\n\n",
+ r>>5, r&31, sz);
+ return;
+ }
+ }
+ }
+ fprintf(stderr, "Error: search for perfect hash failed\n");
+ exit(1);
+}
+
+/* Parse one token of a fold rule. */
+static uint32_t nexttoken(char **pp, int allowlit, int allowany)
+{
+ char *p = *pp;
+ if (p) {
+ uint32_t i;
+ char *q = strchr(p, ' ');
+ if (q) *q++ = '\0';
+ *pp = q;
+ if (allowlit && !strncmp(p, "IRFPM_", 6)) {
+ for (i = 0; irfpm_names[i]; i++)
+ if (!strcmp(irfpm_names[i], p+6))
+ return i;
+ } else if (allowlit && !strncmp(p, "IRFL_", 5)) {
+ for (i = 0; irfield_names[i]; i++)
+ if (!strcmp(irfield_names[i], p+5))
+ return i;
+ } else if (allowlit && !strncmp(p, "IRCALL_", 7)) {
+ for (i = 0; ircall_names[i]; i++)
+ if (!strcmp(ircall_names[i], p+7))
+ return i;
+ } else if (allowlit && !strncmp(p, "IRCONV_", 7)) {
+ for (i = 0; irt_names[i]; i++) {
+ const char *r = strchr(p+7, '_');
+ if (r && !strncmp(irt_names[i], p+7, r-(p+7))) {
+ uint32_t j;
+ for (j = 0; irt_names[j]; j++)
+ if (!strcmp(irt_names[j], r+1))
+ return (i << 5) + j;
+ }
+ }
+ } else if (allowlit && *p >= '0' && *p <= '9') {
+ for (i = 0; *p >= '0' && *p <= '9'; p++)
+ i = i*10 + (*p - '0');
+ if (*p == '\0')
+ return i;
+ } else if (allowany && !strcmp("any", p)) {
+ return allowany;
+ } else {
+ for (i = 0; ir_names[i]; i++)
+ if (!strcmp(ir_names[i], p))
+ return i;
+ }
+ fprintf(stderr, "Error: bad fold definition token \"%s\" at line %d\n", p, lineno);
+ exit(1);
+ }
+ return 0;
+}
+
+/* Parse a fold rule. */
+static void foldrule(char *p)
+{
+ uint32_t op = nexttoken(&p, 0, 0);
+ uint32_t left = nexttoken(&p, 0, 0x7f);
+ uint32_t right = nexttoken(&p, 1, 0x3ff);
+ uint32_t key = (funcidx << 24) | (op << 17) | (left << 10) | right;
+ uint32_t i;
+ if (nkeys >= BUILD_MAX_FOLD) {
+ fprintf(stderr, "Error: too many fold rules, increase BUILD_MAX_FOLD.\n");
+ exit(1);
+ }
+ /* Simple insertion sort to detect duplicates. */
+ for (i = nkeys; i > 0; i--) {
+ if ((foldkeys[i-1]&0xffffff) < (key & 0xffffff))
+ break;
+ if ((foldkeys[i-1]&0xffffff) == (key & 0xffffff)) {
+ fprintf(stderr, "Error: duplicate fold definition at line %d\n", lineno);
+ exit(1);
+ }
+ foldkeys[i] = foldkeys[i-1];
+ }
+ foldkeys[i] = key;
+ nkeys++;
+}
+
+/* Emit C source code for IR folding hash table. */
+void emit_fold(BuildCtx *ctx)
+{
+ char buf[256]; /* We don't care about analyzing lines longer than that. */
+ const char *fname = ctx->args[0];
+ FILE *fp;
+
+ if (fname == NULL) {
+ fprintf(stderr, "Error: missing input filename\n");
+ exit(1);
+ }
+
+ if (fname[0] == '-' && fname[1] == '\0') {
+ fp = stdin;
+ } else {
+ fp = fopen(fname, "r");
+ if (!fp) {
+ fprintf(stderr, "Error: cannot open input file '%s': %s\n",
+ fname, strerror(errno));
+ exit(1);
+ }
+ }
+
+ fprintf(ctx->fp, "/* This is a generated file. DO NOT EDIT! */\n\n");
+ fprintf(ctx->fp, "static const FoldFunc fold_func[] = {\n");
+
+ lineno = 0;
+ funcidx = 0;
+ nkeys = 0;
+ while (fgets(buf, sizeof(buf), fp) != NULL) {
+ lineno++;
+ /* The prefix must be at the start of a line, otherwise it's ignored. */
+ if (!strncmp(buf, FOLDDEF_PREFIX, sizeof(FOLDDEF_PREFIX)-1)) {
+ char *p = buf+sizeof(FOLDDEF_PREFIX)-1;
+ char *q = strchr(p, ')');
+ if (p[0] == '(' && q) {
+ p++;
+ *q = '\0';
+ foldrule(p);
+ } else if ((p[0] == 'F' || p[0] == 'X') && p[1] == '(' && q) {
+ p += 2;
+ *q = '\0';
+ if (funcidx)
+ fprintf(ctx->fp, ",\n");
+ if (p[-2] == 'X')
+ fprintf(ctx->fp, " %s", p);
+ else
+ fprintf(ctx->fp, " fold_%s", p);
+ funcidx++;
+ } else {
+ buf[strlen(buf)-1] = '\0';
+ fprintf(stderr, "Error: unknown fold definition tag %s%s at line %d\n",
+ FOLDDEF_PREFIX, p, lineno);
+ exit(1);
+ }
+ }
+ }
+ fclose(fp);
+ fprintf(ctx->fp, "\n};\n\n");
+
+ makehash(ctx);
+}
+#else
+void emit_fold(BuildCtx *ctx)
+{
+ UNUSED(ctx);
+}
+#endif
+
generated by cgit v1.2.1 (git 2.18.0) at 2024-11-01 10:38:18 +0000