-/*
- * ssa.c: Static single assign form support for the JIT compiler.
+/**
+ * \file
+ * Static single assign form support for the JIT compiler.
*
* Author:
* Dietmar Maurer (dietmar@ximian.com)
*
* (C) 2003 Ximian, Inc.
+ * Copyright 2011 Xamarin, Inc (http://www.xamarin.com)
+ * Licensed under the MIT license. See LICENSE file in the project root for full license information.
*/
#include <config.h>
#include <string.h>
#include <mono/metadata/debug-helpers.h>
#include <mono/metadata/mempool.h>
#include <mono/metadata/mempool-internals.h>
+#include <mono/utils/mono-compiler.h>
#ifndef DISABLE_JIT
#include <alloca.h>
#endif
-#define USE_ORIGINAL_VARS
#define CREATE_PRUNED_SSA
//#define DEBUG_SSA 1
#define NEW_PHI(cfg,dest,val) do { \
- (dest) = mono_mempool_alloc0 ((cfg)->mempool, sizeof (MonoInst)); \
- (dest)->opcode = OP_PHI; \
- (dest)->inst_c0 = (val); \
- (dest)->dreg = (dest)->sreg1 = (dest)->sreg2 = -1; \
+ MONO_INST_NEW ((cfg), (dest), OP_PHI); \
+ (dest)->inst_c0 = (val); \
} while (0)
typedef struct {
record_use (MonoCompile *cfg, MonoInst *var, MonoBasicBlock *bb, MonoInst *ins)
{
MonoMethodVar *info;
- MonoVarUsageInfo *ui = mono_mempool_alloc (cfg->mempool, sizeof (MonoVarUsageInfo));
+ MonoVarUsageInfo *ui = (MonoVarUsageInfo *)mono_mempool_alloc (cfg->mempool, sizeof (MonoVarUsageInfo));
info = MONO_VARINFO (cfg, var->inst_c0);
/**
* mono_ssa_rename_vars:
- *
- * Implement renaming of SSA variables. Also compute def-use information in parallel.
- * @stack_history points to an area of memory which can be used for storing changes
+ * Implement renaming of SSA variables. Also compute def-use information in parallel.
+ * \p stack_history points to an area of memory which can be used for storing changes
* made to the stack, so they can be reverted later.
*/
static void
if (var->opcode == OP_ARG)
originals_used [idx] = TRUE;
- /* FIXME: */
- g_assert (stack_history_len < stack_history_size);
+ if (stack_history_len + 128 > stack_history_size) {
+ stack_history_size += 1024;
+ RenameInfo *new_history = mono_mempool_alloc (cfg->mempool, sizeof (RenameInfo) * stack_history_size);
+ memcpy (new_history, stack_history, stack_history_len * sizeof (RenameInfo));
+ stack_history = new_history;
+ }
+
stack_history [stack_history_len].var = stack [idx];
stack_history [stack_history_len].idx = idx;
stack_history_len ++;
}
else if (G_UNLIKELY (!var && lvreg_defined [ins->dreg] && (ins->dreg >= MONO_MAX_IREGS))) {
/* Perform renaming for local vregs */
- lvreg_stack [ins->dreg] = mono_alloc_preg (cfg);
+ lvreg_stack [ins->dreg] = vreg_is_ref (cfg, ins->dreg) ? mono_alloc_ireg_ref (cfg) : mono_alloc_preg (cfg);
ins->dreg = lvreg_stack [ins->dreg];
}
else
g_assert (!(cfg->comp_done & MONO_COMP_SSA));
- /* we dont support methods containing exception clauses */
- g_assert (mono_method_get_header (cfg->method)->num_clauses == 0);
g_assert (!cfg->disable_ssa);
if (cfg->verbose_level >= 4)
mono_compile_dominator_info (cfg, MONO_COMP_DOM | MONO_COMP_IDOM | MONO_COMP_DFRONTIER);
bitsize = mono_bitset_alloc_size (cfg->num_bblocks, 0);
- buf = buf_start = g_malloc0 (mono_bitset_alloc_size (cfg->num_bblocks, 0) * cfg->num_varinfo);
+ buf = buf_start = (guint8 *)g_malloc0 (mono_bitset_alloc_size (cfg->num_bblocks, 0) * cfg->num_varinfo);
for (i = 0; i < cfg->num_varinfo; ++i) {
vinfo [i].def_in = mono_bitset_mem_new (buf, cfg->num_bblocks, 0);
MonoInst *var = cfg->varinfo [i];
#if SIZEOF_REGISTER == 4
- if (var->type == STACK_I8)
+ if (var->type == STACK_I8 && !COMPILE_LLVM (cfg))
continue;
#endif
if (var->flags & (MONO_INST_VOLATILE|MONO_INST_INDIRECT))
/* fixme: create pruned SSA? we would need liveness information for that */
- if (bb == cfg->bb_exit)
+ if (bb == cfg->bb_exit && !COMPILE_LLVM (cfg))
continue;
if ((cfg->comp_done & MONO_COMP_LIVENESS) && !mono_bitset_test_fast (bb->live_in_set, i)) {
break;
case STACK_VTYPE:
ins->opcode = MONO_CLASS_IS_SIMD (cfg, var->klass) ? OP_XPHI : OP_VPHI;
- ins->klass = var->klass;
break;
}
- ins->inst_phi_args = mono_mempool_alloc0 (cfg->mempool, sizeof (int) * (cfg->bblocks [idx]->in_count + 1));
+ if (var->inst_vtype->byref)
+ ins->klass = mono_defaults.int_class;
+ else
+ ins->klass = var->klass;
+
+ ins->inst_phi_args = (int *)mono_mempool_alloc0 (cfg->mempool, sizeof (int) * (cfg->bblocks [idx]->in_count + 1));
ins->inst_phi_args [0] = cfg->bblocks [idx]->in_count;
/* For debugging */
/* Renaming phase */
- stack = alloca (sizeof (MonoInst *) * cfg->num_varinfo);
+ stack = (MonoInst **)alloca (sizeof (MonoInst *) * cfg->num_varinfo);
memset (stack, 0, sizeof (MonoInst *) * cfg->num_varinfo);
lvreg_stack = g_new0 (guint32, cfg->next_vreg);
mono_ssa_rename_vars (cfg, cfg->num_varinfo, cfg->bb_entry, originals, stack, lvreg_stack, lvreg_defined, stack_history, stack_history_size);
g_free (stack_history);
g_free (originals);
+ g_free (lvreg_stack);
+ g_free (lvreg_defined);
if (cfg->verbose_level >= 4)
printf ("\nEND COMPUTE SSA.\n\n");
cfg->comp_done |= MONO_COMP_SSA;
}
+/*
+ * mono_ssa_remove_gsharedvt:
+ *
+ * Same as mono_ssa_remove, but only remove phi nodes for gsharedvt variables.
+ */
void
-mono_ssa_remove (MonoCompile *cfg)
+mono_ssa_remove_gsharedvt (MonoCompile *cfg)
{
MonoInst *ins, *var, *move;
int i, j, first;
+ /*
+ * When compiling gsharedvt code, we need to get rid of the VPHI instructions,
+ * since they cannot be handled later in the llvm backend.
+ */
+ g_assert (cfg->comp_done & MONO_COMP_SSA);
+
+ for (i = 0; i < cfg->num_bblocks; ++i) {
+ MonoBasicBlock *bb = cfg->bblocks [i];
+
+ if (cfg->verbose_level >= 4)
+ printf ("\nREMOVE SSA %d:\n", bb->block_num);
+
+ for (ins = bb->code; ins; ins = ins->next) {
+ if (!(MONO_IS_PHI (ins) && ins->opcode == OP_VPHI && mini_is_gsharedvt_variable_type (&ins->klass->byval_arg)))
+ continue;
+
+ g_assert (ins->inst_phi_args [0] == bb->in_count);
+ var = get_vreg_to_inst (cfg, ins->dreg);
+
+ /* Check for PHI nodes where all the inputs are the same */
+ first = ins->inst_phi_args [1];
+
+ for (j = 1; j < bb->in_count; ++j)
+ if (first != ins->inst_phi_args [j + 1])
+ break;
+
+ if ((bb->in_count > 1) && (j == bb->in_count)) {
+ ins->opcode = op_phi_to_move (ins->opcode);
+ if (ins->opcode == OP_VMOVE)
+ g_assert (ins->klass);
+ ins->sreg1 = first;
+ } else {
+ for (j = 0; j < bb->in_count; j++) {
+ MonoBasicBlock *pred = bb->in_bb [j];
+ int sreg = ins->inst_phi_args [j + 1];
+
+ if (cfg->verbose_level >= 4)
+ printf ("\tADD R%d <- R%d in BB%d\n", var->dreg, sreg, pred->block_num);
+ if (var->dreg != sreg) {
+ MONO_INST_NEW (cfg, move, op_phi_to_move (ins->opcode));
+ if (move->opcode == OP_VMOVE) {
+ g_assert (ins->klass);
+ move->klass = ins->klass;
+ }
+ move->dreg = var->dreg;
+ move->sreg1 = sreg;
+ mono_add_ins_to_end (pred, move);
+ }
+ }
+
+ NULLIFY_INS (ins);
+ }
+ }
+ }
+}
+
+void
+mono_ssa_remove (MonoCompile *cfg)
+{
+ MonoInst *ins, *var, *move;
+ int bbindex, i, j, first;
+
g_assert (cfg->comp_done & MONO_COMP_SSA);
for (i = 0; i < cfg->num_bblocks; ++i) {
}
}
- ins->opcode = OP_NOP;
- ins->dreg = -1;
+ NULLIFY_INS (ins);
}
}
}
* can coalesce them into the original variable.
*/
- for (i = 0; i < cfg->num_bblocks; ++i) {
- MonoBasicBlock *bb = cfg->bblocks [i];
+ for (bbindex = 0; bbindex < cfg->num_bblocks; ++bbindex) {
+ MonoBasicBlock *bb = cfg->bblocks [bbindex];
for (ins = bb->code; ins; ins = ins->next) {
const char *spec = INS_INFO (ins->opcode);
- int num_sregs, j;
+ int num_sregs;
int sregs [MONO_MAX_SRC_REGS];
if (ins->opcode == OP_NOP)
}
num_sregs = mono_inst_get_src_registers (ins, sregs);
- for (j = 0; j < num_sregs; ++j) {
+ for (i = 0; i < num_sregs; ++i) {
MonoInst *var = get_vreg_to_inst (cfg, sregs [i]);
if (var) {
/* Rewrite all uses of var to be uses of var2 */
int dreg = var->dreg;
int sreg1 = var2->dreg;
- const char *spec;
l = info->uses;
while (l) {
int num_sregs;
int sregs [MONO_MAX_SRC_REGS];
- spec = INS_INFO (ins->opcode);
-
num_sregs = mono_inst_get_src_registers (ins, sregs);
for (i = 0; i < num_sregs; ++i) {
if (sregs [i] == dreg)
if (MONO_IS_JUMP_TABLE (ins)) {
int i;
- MonoJumpInfoBBTable *table = MONO_JUMP_TABLE_FROM_INS (ins);
+ MonoJumpInfoBBTable *table = (MonoJumpInfoBBTable *)MONO_JUMP_TABLE_FROM_INS (ins);
if (!ins->next || ins->next->opcode != OP_PADD) {
/* The PADD was optimized away */
if (ins->opcode == OP_SWITCH) {
int i;
- MonoJumpInfoBBTable *table = ins->inst_p0;
+ MonoJumpInfoBBTable *table = (MonoJumpInfoBBTable *)ins->inst_p0;
for (i = 0; i < table->table_size; i++)
if (table->table [i])
if (MONO_IS_JUMP_TABLE (ins)) {
int i;
- MonoJumpInfoBBTable *table = MONO_JUMP_TABLE_FROM_INS (ins);
+ MonoJumpInfoBBTable *table = (MonoJumpInfoBBTable *)MONO_JUMP_TABLE_FROM_INS (ins);
if (!ins->next || ins->next->opcode != OP_PADD) {
/* The PADD was optimized away */
/* Unlink target bblocks */
for (i = 0; i < table->table_size; ++i) {
- if (i != idx) {
+ if (table->table [i] != table->table [idx]) {
remove_bb_from_phis (cfg, bb, table->table [i]);
mono_unlink_bblock (cfg, bb, table->table [i]);
}
info->cpstate = 2;
}
+ for (bb = cfg->bb_entry->next_bb; bb; bb = bb->next_bb) {
+ /*
+ * FIXME: This should be bb->flags & BB_FLAG_EXCEPTION_HANDLER, but
+ * that would still allow unreachable try's to be removed.
+ */
+ if (bb->region)
+ add_cprop_bb (cfg, bb, &bblock_list);
+ }
+
cvars = NULL;
while (bblock_list) {
g_assert (bb->flags & BB_REACHABLE);
- if (bb->out_count == 1) {
- if (!(bb->out_bb [0]->flags & BB_REACHABLE)) {
- bb->out_bb [0]->flags |= BB_REACHABLE;
- bblock_list = g_list_prepend (bblock_list, bb->out_bb [0]);
- }
+ /*
+ * Some bblocks are linked to 2 others even through they fall through to the
+ * next bblock.
+ */
+ if (!(bb->last_ins && MONO_IS_BRANCH_OP (bb->last_ins))) {
+ for (i = 0; i < bb->out_count; ++i)
+ add_cprop_bb (cfg, bb->out_bb [i], &bblock_list);
}
if (cfg->verbose_level > 1)
MonoInst *src_var = get_vreg_to_inst (cfg, def->sreg1);
if (src_var && !(src_var->flags & (MONO_INST_VOLATILE|MONO_INST_INDIRECT)))
add_to_dce_worklist (cfg, info, MONO_VARINFO (cfg, src_var->inst_c0), &work_list);
- def->opcode = OP_NOP;
- def->dreg = def->sreg1 = def->sreg2 = -1;
+ NULLIFY_INS (def);
info->reg = -1;
} else if ((def->opcode == OP_ICONST) || (def->opcode == OP_I8CONST) || MONO_IS_ZERO (def)) {
- def->opcode = OP_NOP;
- def->dreg = def->sreg1 = def->sreg2 = -1;
+ NULLIFY_INS (def);
info->reg = -1;
} else if (MONO_IS_PHI (def)) {
int j;
MonoMethodVar *u = MONO_VARINFO (cfg, get_vreg_to_inst (cfg, def->inst_phi_args [j])->inst_c0);
add_to_dce_worklist (cfg, info, u, &work_list);
}
- def->opcode = OP_NOP;
- def->dreg = def->sreg1 = def->sreg2 = -1;
+ NULLIFY_INS (def);
info->reg = -1;
}
else if (def->opcode == OP_NOP) {
}
#endif
-#endif /* DISABLE_JIT */
+void
+mono_ssa_loop_invariant_code_motion (MonoCompile *cfg)
+{
+ MonoBasicBlock *bb, *h, *idom;
+ MonoInst *ins, *n, *tins;
+ int i;
+
+ g_assert (cfg->comp_done & MONO_COMP_SSA);
+ if (!(cfg->comp_done & MONO_COMP_LOOPS) || !(cfg->comp_done & MONO_COMP_SSA_DEF_USE))
+ return;
+
+ for (bb = cfg->bb_entry->next_bb; bb; bb = bb->next_bb) {
+ GList *lp = bb->loop_blocks;
+
+ if (!lp)
+ continue;
+ h = (MonoBasicBlock *)lp->data;
+ if (bb != h)
+ continue;
+ MONO_BB_FOR_EACH_INS_SAFE (bb, n, ins) {
+ /*
+ * Try to move instructions out of loop headers into the preceeding bblock.
+ */
+ if (ins->opcode == OP_LDLEN || ins->opcode == OP_STRLEN || ins->opcode == OP_CHECK_THIS || ins->opcode == OP_AOTCONST || ins->opcode == OP_GENERIC_CLASS_INIT) {
+ gboolean skip;
+ int sreg;
+
+ idom = h->idom;
+ /*
+ * h->nesting is needed to work around:
+ * http://llvm.org/bugs/show_bug.cgi?id=17868
+ */
+ if (!(idom && idom->last_ins && idom->last_ins->opcode == OP_BR && idom->last_ins->inst_target_bb == h && h->nesting == 1)) {
+ continue;
+ }
+
+ /*
+ * Make sure there are no instructions with side effects before ins.
+ */
+ skip = FALSE;
+ MONO_BB_FOR_EACH_INS (bb, tins) {
+ if (tins == ins)
+ break;
+ if (!MONO_INS_HAS_NO_SIDE_EFFECT (tins)) {
+ skip = TRUE;
+ break;
+ }
+ }
+ if (skip) {
+ /*
+ printf ("%s\n", mono_method_full_name (cfg->method, TRUE));
+ mono_print_ins (tins);
+ */
+ continue;
+ }
+
+ /* Make sure we don't move the instruction before the def of its sreg */
+ if (ins->opcode == OP_LDLEN || ins->opcode == OP_STRLEN || ins->opcode == OP_CHECK_THIS)
+ sreg = ins->sreg1;
+ else
+ sreg = -1;
+ if (sreg != -1) {
+ MonoInst *tins, *var;
+
+ skip = FALSE;
+ for (tins = ins->prev; tins; tins = tins->prev) {
+ const char *spec = INS_INFO (tins->opcode);
+
+ if (tins->opcode == OP_MOVE && tins->dreg == sreg) {
+ sreg = tins->sreg1;
+ } if (spec [MONO_INST_DEST] != ' ' && tins->dreg == sreg) {
+ skip = TRUE;
+ break;
+ }
+ }
+ if (skip)
+ continue;
+ var = get_vreg_to_inst (cfg, sreg);
+ if (var && (var->flags & (MONO_INST_VOLATILE|MONO_INST_INDIRECT)))
+ continue;
+ ins->sreg1 = sreg;
+ }
+
+ if (cfg->verbose_level > 1) {
+ printf ("licm in BB%d on ", bb->block_num);
+ mono_print_ins (ins);
+ }
+ //{ static int count = 0; count ++; printf ("%d\n", count); }
+ MONO_REMOVE_INS (bb, ins);
+ mono_bblock_insert_before_ins (idom, idom->last_ins, ins);
+ if (ins->opcode == OP_LDLEN || ins->opcode == OP_STRLEN)
+ idom->has_array_access = TRUE;
+ }
+ }
+ }
+
+ cfg->comp_done &= ~MONO_COMP_SSA_DEF_USE;
+ for (i = 0; i < cfg->num_varinfo; i++) {
+ MonoMethodVar *info = MONO_VARINFO (cfg, i);
+ info->def = NULL;
+ info->uses = NULL;
+ }
+}
+
+#else /* !DISABLE_JIT */
+
+MONO_EMPTY_SOURCE_FILE (ssa);
+
+#endif /* !DISABLE_JIT */