--- /dev/null
+/*
+ * Copyright 2010 Tom Stellard <tstellar@gmail.com>
+ *
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial
+ * portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+/**
+ * \file
+ */
+
+#include "radeon_rename_regs.h"
+
+#include "radeon_compiler.h"
+#include "radeon_dataflow.h"
+
+struct reg_rename {
+ int old_index;
+ int new_index;
+ int temp_index;
+};
+
+static void rename_reg(void * data, struct rc_instruction * inst,
+ rc_register_file * file, unsigned int * index)
+{
+ struct reg_rename *r = data;
+
+ if(r->old_index == *index && *file == RC_FILE_TEMPORARY) {
+ *index = r->new_index;
+ }
+ else if(r->new_index == *index && *file == RC_FILE_TEMPORARY) {
+ *index = r->temp_index;
+ }
+}
+
+static void rename_all(
+ struct radeon_compiler *c,
+ struct rc_instruction * start,
+ unsigned int old,
+ unsigned int new,
+ unsigned int temp)
+{
+ struct rc_instruction * inst;
+ struct reg_rename r;
+ r.old_index = old;
+ r.new_index = new;
+ r.temp_index = temp;
+ for(inst = start; inst != &c->Program.Instructions;
+ inst = inst->Next) {
+ rc_remap_registers(inst, rename_reg, &r);
+ }
+}
+
+/**
+ * This function renames registers in an attempt to get the code close to
+ * SSA form. After this function has completed, most of the register are only
+ * written to one time, with a few exceptions. For example, this block of code
+ * will not be modified by this function:
+ * Mov Temp[0].x Const[0].x
+ * Mov Temp[0].y Const[0].y
+ * Basically, destination registers will be renamed if:
+ * 1. There have been no previous writes to that register
+ * or
+ * 2. If the instruction is writting to the exact components (no more, no less)
+ * of a register that has been written to by previous instructions.
+ *
+ * This function assumes all the instructions are still of type
+ * RC_INSTRUCTION_NORMAL.
+ */
+void rc_rename_regs(struct radeon_compiler * c)
+{
+ unsigned int cur_index = 0;
+ unsigned int icount;
+ struct rc_instruction * inst;
+ unsigned int * masks;
+
+ /* The number of instructions in the program is also the maximum
+ * number of temp registers that could potentially be used. */
+ icount = rc_recompute_ips(c);
+ masks = memory_pool_malloc(&c->Pool, icount * sizeof(unsigned int));
+ memset(masks, 0, icount * sizeof(unsigned int));
+
+ for(inst = c->Program.Instructions.Next;
+ inst != &c->Program.Instructions;
+ inst = inst->Next) {
+ const struct rc_opcode_info * info;
+ if(inst->Type != RC_INSTRUCTION_NORMAL) {
+ rc_error(c, "%s only works with normal instructions.",
+ __FUNCTION__);
+ return;
+ }
+ unsigned int old_index, temp_index;
+ struct rc_dst_register * dst = &inst->U.I.DstReg;
+ info = rc_get_opcode_info(inst->U.I.Opcode);
+ if(!info->HasDstReg || dst->File != RC_FILE_TEMPORARY) {
+ continue;
+ }
+ if(dst->Index >= icount || !masks[dst->Index] ||
+ masks[dst->Index] == dst->WriteMask) {
+ old_index = dst->Index;
+ /* We need to set dst->Index here so get free temporary
+ * will work. */
+ dst->Index = cur_index++;
+ temp_index = rc_find_free_temporary(c);
+ rename_all(c, inst->Next, old_index,
+ dst->Index, temp_index);
+ }
+ assert(dst->Index < icount);
+ masks[dst->Index] |= dst->WriteMask;
+ }
+}
projects / mesa.git / commitdiff