* The idea of instruction compaction is that most instructions use a tiny
* subset of the GPU functionality, so we can encode what would be a 16 byte
* instruction in 8 bytes using some lookup tables for various fields.
+ *
+ *
+ * Instruction compaction capabilities vary subtly by generation.
+ *
+ * G45's support for instruction compaction is very limited. Jump counts on
+ * this generation are in units of 16-byte uncompacted instructions. As such,
+ * all jump targets must be 16-byte aligned. Also, all instructions must be
+ * naturally aligned, i.e. uncompacted instructions must be 16-byte aligned.
+ * A G45-only instruction, NENOP, must be used to provide padding to align
+ * uncompacted instructions.
+ *
+ * Gen5 removes these restrictions and changes jump counts to be in units of
+ * 8-byte compacted instructions, allowing jump targets to be only 8-byte
+ * aligned. Uncompacted instructions can also be placed on 8-byte boundaries.
+ *
+ * Gen6 adds the ability to compact instructions with a limited range of
+ * immediate values. Compactable immediates have 12 unrestricted bits, and a
+ * 13th bit that's replicated through the high 20 bits, to create the 32-bit
+ * value of DW3 in the uncompacted instruction word.
+ *
+ * On Gen7 we can compact some control flow instructions with a small positive
+ * immediate in the low bits of DW3, like ENDIF with the JIP field. Other
+ * control flow instructions with UIP cannot be compacted, because of the
+ * replicated 13th bit. No control flow instructions can be compacted on Gen6
+ * since the jump count field is not in DW3.
+ *
+ * break JIP/UIP
+ * cont JIP/UIP
+ * halt JIP/UIP
+ * if JIP/UIP
+ * else JIP (plus UIP on BDW+)
+ * endif JIP
+ * while JIP (must be negative)
+ *
+ * Gen 8 adds support for compacting 3-src instructions.
*/
#include "brw_context.h"
(brw_inst_bits(src, 34, 32) << 21) | /* 3b */
(brw_inst_bits(src, 28, 8)); /* 21b */
- if (brw->is_cherryview)
+ if (brw->gen >= 9 || brw->is_cherryview)
uncompacted |= brw_inst_bits(src, 36, 35) << 24; /* 2b */
for (int i = 0; i < ARRAY_SIZE(gen8_3src_control_index_table); i++) {
(brw_inst_bits(src, 72, 65) << 19) | /* 8b */
(brw_inst_bits(src, 55, 37)); /* 19b */
- if (brw->is_cherryview) {
+ if (brw->gen >= 9 || brw->is_cherryview) {
uncompacted |=
(brw_inst_bits(src, 126, 125) << 47) | /* 2b */
(brw_inst_bits(src, 105, 104) << 45) | /* 2b */
assert(brw_inst_cmpt_control(brw, src) == 0);
- if (brw_inst_opcode(brw, src) == BRW_OPCODE_IF ||
- brw_inst_opcode(brw, src) == BRW_OPCODE_IFF ||
- brw_inst_opcode(brw, src) == BRW_OPCODE_ELSE ||
- brw_inst_opcode(brw, src) == BRW_OPCODE_ENDIF ||
- brw_inst_opcode(brw, src) == BRW_OPCODE_HALT ||
- brw_inst_opcode(brw, src) == BRW_OPCODE_DO ||
- brw_inst_opcode(brw, src) == BRW_OPCODE_WHILE) {
- /* FINISHME: The fixup code below, and brw_set_uip_jip and friends, needs
- * to be able to handle compacted flow control instructions..
- */
- return false;
- }
-
if (is_3src(brw_inst_opcode(brw, src))) {
if (brw->gen >= 8) {
memset(&temp, 0, sizeof(temp));
brw_inst_set_bits(dst, 34, 32, (uncompacted >> 21) & 0x7);
brw_inst_set_bits(dst, 28, 8, (uncompacted >> 0) & 0x1fffff);
- if (brw->is_cherryview)
+ if (brw->gen >= 9 || brw->is_cherryview)
brw_inst_set_bits(dst, 36, 35, (uncompacted >> 24) & 0x3);
}
brw_inst_set_bits(dst, 72, 65, (uncompacted >> 19) & 0xff);
brw_inst_set_bits(dst, 55, 37, (uncompacted >> 0) & 0x7ffff);
- if (brw->is_cherryview) {
+ if (brw->gen >= 9 || brw->is_cherryview) {
brw_inst_set_bits(dst, 126, 125, (uncompacted >> 47) & 0x3);
brw_inst_set_bits(dst, 105, 104, (uncompacted >> 45) & 0x3);
brw_inst_set_bits(dst, 84, 84, (uncompacted >> 44) & 0x1);
* - bytes on Gen8+; and
* - compacted instructions on Gen6+.
*/
- int32_t jip = brw_inst_jip(brw, insn);
- int32_t jip_compacted = jip / (brw->gen >= 8 ? sizeof(brw_compact_inst) : 1);
- int32_t jip_uncompacted = jip / (brw->gen >= 8 ? sizeof(brw_inst) : 2);
+ int shift = brw->gen >= 8 ? 3 : 0;
+
+ int32_t jip_compacted = brw_inst_jip(brw, insn) >> shift;
jip_compacted -= compacted_between(this_old_ip,
- this_old_ip + jip_uncompacted,
+ this_old_ip + (jip_compacted / 2),
compacted_counts);
- brw_inst_set_jip(brw, insn,
- jip_compacted * (brw->gen >= 8 ? sizeof(brw_compact_inst) : 1));
+ brw_inst_set_jip(brw, insn, jip_compacted << shift);
if (brw_inst_opcode(brw, insn) == BRW_OPCODE_ENDIF ||
brw_inst_opcode(brw, insn) == BRW_OPCODE_WHILE ||
(brw_inst_opcode(brw, insn) == BRW_OPCODE_ELSE && brw->gen <= 7))
return;
- int32_t uip = brw_inst_uip(brw, insn);
- int32_t uip_compacted = uip / (brw->gen >= 8 ? sizeof(brw_compact_inst) : 1);
- int32_t uip_uncompacted = uip / (brw->gen >= 8 ? sizeof(brw_inst) : 2);
+ int32_t uip_compacted = brw_inst_uip(brw, insn) >> shift;
uip_compacted -= compacted_between(this_old_ip,
- this_old_ip + uip_uncompacted,
+ this_old_ip + (uip_compacted / 2),
compacted_counts);
- brw_inst_set_uip(brw, insn,
- uip_compacted * (brw->gen >= 8 ? sizeof(brw_compact_inst) : 1));
+ brw_inst_set_uip(brw, insn, uip_compacted << shift);
}
static void
* - uncompacted instructions on G45; and
* - compacted instructions on Gen5.
*/
- int jump_count = brw_inst_gen4_jump_count(brw, insn);
- int jump_count_compacted = jump_count * (brw->is_g4x ? 2 : 1);
- int jump_count_uncompacted = jump_count / (brw->is_g4x ? 1 : 2);
+ int shift = brw->is_g4x ? 1 : 0;
- int target_old_ip = this_old_ip + jump_count_uncompacted;
+ int jump_count_compacted = brw_inst_gen4_jump_count(brw, insn) << shift;
+
+ int target_old_ip = this_old_ip + (jump_count_compacted / 2);
int this_compacted_count = compacted_counts[this_old_ip];
int target_compacted_count = compacted_counts[target_old_ip];
jump_count_compacted -= (target_compacted_count - this_compacted_count);
- brw_inst_set_gen4_jump_count(brw, insn, jump_count_compacted /
- (brw->is_g4x ? 2 : 1));
+ brw_inst_set_gen4_jump_count(brw, insn, jump_count_compacted >> shift);
}
void
assert(gen8_src_index_table[ARRAY_SIZE(gen8_src_index_table) - 1] != 0);
switch (brw->gen) {
+ case 9:
case 8:
control_index_table = gen8_control_index_table;
datatype_table = gen8_datatype_table;
brw_inst *insn = store + offset;
int this_old_ip = old_ip[offset / sizeof(brw_compact_inst)];
int this_compacted_count = compacted_counts[this_old_ip];
- int target_old_ip, target_compacted_count;
switch (brw_inst_opcode(brw, insn)) {
case BRW_OPCODE_BREAK:
case BRW_OPCODE_ENDIF:
case BRW_OPCODE_WHILE:
if (brw->gen >= 7) {
- update_uip_jip(brw, insn, this_old_ip, compacted_counts);
+ if (brw_inst_cmpt_control(brw, insn)) {
+ brw_inst uncompacted;
+ brw_uncompact_instruction(brw, &uncompacted,
+ (brw_compact_inst *)insn);
+
+ update_uip_jip(brw, &uncompacted, this_old_ip, compacted_counts);
+
+ bool ret = brw_try_compact_instruction(brw,
+ (brw_compact_inst *)insn,
+ &uncompacted);
+ assert(ret); (void)ret;
+ } else {
+ update_uip_jip(brw, insn, this_old_ip, compacted_counts);
+ }
} else if (brw->gen == 6) {
+ assert(!brw_inst_cmpt_control(brw, insn));
+
/* Jump Count is in units of compacted instructions on Gen6. */
int jump_count_compacted = brw_inst_gen6_jump_count(brw, insn);
- int jump_count_uncompacted = jump_count_compacted / 2;
- target_old_ip = this_old_ip + jump_count_uncompacted;
- target_compacted_count = compacted_counts[target_old_ip];
+ int target_old_ip = this_old_ip + (jump_count_compacted / 2);
+ int target_compacted_count = compacted_counts[target_old_ip];
jump_count_compacted -= (target_compacted_count - this_compacted_count);
brw_inst_set_gen6_jump_count(brw, insn, jump_count_compacted);
} else {
brw_inst_dst_da_reg_nr(brw, insn) == BRW_ARF_IP) {
assert(brw_inst_src1_reg_file(brw, insn) == BRW_IMMEDIATE_VALUE);
- int jump = brw_inst_imm_d(brw, insn);
- int jump_compacted = jump / sizeof(brw_compact_inst);
- int jump_uncompacted = jump / sizeof(brw_inst);
+ int shift = 3;
+ int jump_compacted = brw_inst_imm_d(brw, insn) >> shift;
- target_old_ip = this_old_ip + jump_uncompacted;
- target_compacted_count = compacted_counts[target_old_ip];
+ int target_old_ip = this_old_ip + (jump_compacted / 2);
+ int target_compacted_count = compacted_counts[target_old_ip];
jump_compacted -= (target_compacted_count - this_compacted_count);
- brw_inst_set_imm_ud(brw, insn, jump_compacted *
- sizeof(brw_compact_inst));
+ brw_inst_set_imm_ud(brw, insn, jump_compacted << shift);
}
break;
}
projects / mesa.git / blobdiff