[Mesa-dev] [PATCH 02/25] i965: Move compaction "prepass" into brw_eu_compact.c
Matt Turner
mattst88 at gmail.com
Fri Aug 4 17:31:34 UTC 2017
---
src/intel/compiler/brw_eu_compact.c | 82 ++++++++++++++++++++++++++++++++++++-
src/intel/compiler/brw_eu_emit.c | 72 +-------------------------------
2 files changed, 82 insertions(+), 72 deletions(-)
diff --git a/src/intel/compiler/brw_eu_compact.c b/src/intel/compiler/brw_eu_compact.c
index a940e214f2..bf57ddf85c 100644
--- a/src/intel/compiler/brw_eu_compact.c
+++ b/src/intel/compiler/brw_eu_compact.c
@@ -956,6 +956,83 @@ is_compactable_immediate(unsigned imm)
}
/**
+ * Applies some small changes to instruction types to increase chances of
+ * compaction.
+ */
+static brw_inst
+precompact(const struct gen_device_info *devinfo, brw_inst inst)
+{
+ if (brw_inst_src0_reg_file(devinfo, &inst) != BRW_IMMEDIATE_VALUE)
+ return inst;
+
+ /* The Bspec's section titled "Non-present Operands" claims that if src0
+ * is an immediate that src1's type must be the same as that of src0.
+ *
+ * The SNB+ DataTypeIndex instruction compaction tables contain mappings
+ * that do not follow this rule. E.g., from the IVB/HSW table:
+ *
+ * DataTypeIndex 18-Bit Mapping Mapped Meaning
+ * 3 001000001011111101 r:f | i:vf | a:ud | <1> | dir |
+ *
+ * And from the SNB table:
+ *
+ * DataTypeIndex 18-Bit Mapping Mapped Meaning
+ * 8 001000000111101100 a:w | i:w | a:ud | <1> | dir |
+ *
+ * Neither of these cause warnings from the simulator when used,
+ * compacted or otherwise. In fact, all compaction mappings that have an
+ * immediate in src0 use a:ud for src1.
+ *
+ * The GM45 instruction compaction tables do not contain mapped meanings
+ * so it's not clear whether it has the restriction. We'll assume it was
+ * lifted on SNB. (FINISHME: decode the GM45 tables and check.)
+ *
+ * Don't do any of this for 64-bit immediates, since the src1 fields
+ * overlap with the immediate and setting them would overwrite the
+ * immediate we set.
+ */
+ if (devinfo->gen >= 6 &&
+ !(devinfo->is_haswell &&
+ brw_inst_opcode(devinfo, &inst) == BRW_OPCODE_DIM) &&
+ !(devinfo->gen >= 8 &&
+ (brw_inst_src0_reg_type(devinfo, &inst) == GEN8_HW_REG_IMM_TYPE_DF ||
+ brw_inst_src0_reg_type(devinfo, &inst) == GEN8_HW_REG_TYPE_UQ ||
+ brw_inst_src0_reg_type(devinfo, &inst) == GEN8_HW_REG_TYPE_Q))) {
+ brw_inst_set_src1_reg_type(devinfo, &inst, BRW_HW_REG_TYPE_UD);
+ }
+
+ /* Compacted instructions only have 12-bits (plus 1 for the other 20)
+ * for immediate values. Presumably the hardware engineers realized
+ * that the only useful floating-point value that could be represented
+ * in this format is 0.0, which can also be represented as a VF-typed
+ * immediate, so they gave us the previously mentioned mapping on IVB+.
+ *
+ * Strangely, we do have a mapping for imm:f in src1, so we don't need
+ * to do this there.
+ *
+ * If we see a 0.0:F, change the type to VF so that it can be compacted.
+ */
+ if (brw_inst_imm_ud(devinfo, &inst) == 0x0 &&
+ brw_inst_src0_reg_type(devinfo, &inst) == BRW_HW_REG_TYPE_F &&
+ brw_inst_dst_reg_type(devinfo, &inst) != GEN7_HW_REG_NON_IMM_TYPE_DF) {
+ brw_inst_set_src0_reg_type(devinfo, &inst, BRW_HW_REG_IMM_TYPE_VF);
+ }
+
+ /* There are no mappings for dst:d | i:d, so if the immediate is suitable
+ * set the types to :UD so the instruction can be compacted.
+ */
+ if (is_compactable_immediate(brw_inst_imm_ud(devinfo, &inst)) &&
+ brw_inst_cond_modifier(devinfo, &inst) == BRW_CONDITIONAL_NONE &&
+ brw_inst_src0_reg_type(devinfo, &inst) == BRW_HW_REG_TYPE_D &&
+ brw_inst_dst_reg_type(devinfo, &inst) == BRW_HW_REG_TYPE_D) {
+ brw_inst_set_src0_reg_type(devinfo, &inst, BRW_HW_REG_TYPE_UD);
+ brw_inst_set_dst_reg_type(devinfo, &inst, BRW_HW_REG_TYPE_UD);
+ }
+
+ return inst;
+}
+
+/**
* Tries to compact instruction src into dst.
*
* It doesn't modify dst unless src is compactable, which is relied on by
@@ -1427,9 +1504,10 @@ brw_compact_instructions(struct brw_codegen *p, int start_offset,
old_ip[offset / sizeof(brw_compact_inst)] = src_offset / sizeof(brw_inst);
compacted_counts[src_offset / sizeof(brw_inst)] = compacted_count;
- brw_inst saved = *src;
+ brw_inst inst = precompact(devinfo, *src);
+ brw_inst saved = inst;
- if (brw_try_compact_instruction(devinfo, dst, src)) {
+ if (brw_try_compact_instruction(devinfo, dst, &inst)) {
compacted_count++;
if (INTEL_DEBUG) {
diff --git a/src/intel/compiler/brw_eu_emit.c b/src/intel/compiler/brw_eu_emit.c
index 0b0d67a5c5..8a6ec035cc 100644
--- a/src/intel/compiler/brw_eu_emit.c
+++ b/src/intel/compiler/brw_eu_emit.c
@@ -356,16 +356,6 @@ validate_reg(const struct gen_device_info *devinfo,
/* 10. Check destination issues. */
}
-static bool
-is_compactable_immediate(unsigned imm)
-{
- /* We get the low 12 bits as-is. */
- imm &= ~0xfff;
-
- /* We get one bit replicated through the top 20 bits. */
- return imm == 0 || imm == 0xfffff000;
-}
-
void
brw_set_src0(struct brw_codegen *p, brw_inst *inst, struct brw_reg reg)
{
@@ -408,69 +398,11 @@ brw_set_src0(struct brw_codegen *p, brw_inst *inst, struct brw_reg reg)
else
brw_inst_set_imm_ud(devinfo, inst, reg.ud);
- /* The Bspec's section titled "Non-present Operands" claims that if src0
- * is an immediate that src1's type must be the same as that of src0.
- *
- * The SNB+ DataTypeIndex instruction compaction tables contain mappings
- * that do not follow this rule. E.g., from the IVB/HSW table:
- *
- * DataTypeIndex 18-Bit Mapping Mapped Meaning
- * 3 001000001011111101 r:f | i:vf | a:ud | <1> | dir |
- *
- * And from the SNB table:
- *
- * DataTypeIndex 18-Bit Mapping Mapped Meaning
- * 8 001000000111101100 a:w | i:w | a:ud | <1> | dir |
- *
- * Neither of these cause warnings from the simulator when used,
- * compacted or otherwise. In fact, all compaction mappings that have an
- * immediate in src0 use a:ud for src1.
- *
- * The GM45 instruction compaction tables do not contain mapped meanings
- * so it's not clear whether it has the restriction. We'll assume it was
- * lifted on SNB. (FINISHME: decode the GM45 tables and check.)
- *
- * Don't do any of this for 64-bit immediates, since the src1 fields
- * overlap with the immediate and setting them would overwrite the
- * immediate we set.
- */
if (type_sz(reg.type) < 8) {
brw_inst_set_src1_reg_file(devinfo, inst,
BRW_ARCHITECTURE_REGISTER_FILE);
- if (devinfo->gen < 6) {
- brw_inst_set_src1_reg_type(devinfo, inst,
- brw_inst_src0_reg_type(devinfo, inst));
- } else {
- brw_inst_set_src1_reg_type(devinfo, inst, BRW_HW_REG_TYPE_UD);
- }
- }
-
- /* Compacted instructions only have 12-bits (plus 1 for the other 20)
- * for immediate values. Presumably the hardware engineers realized
- * that the only useful floating-point value that could be represented
- * in this format is 0.0, which can also be represented as a VF-typed
- * immediate, so they gave us the previously mentioned mapping on IVB+.
- *
- * Strangely, we do have a mapping for imm:f in src1, so we don't need
- * to do this there.
- *
- * If we see a 0.0:F, change the type to VF so that it can be compacted.
- */
- if (brw_inst_imm_ud(devinfo, inst) == 0x0 &&
- brw_inst_src0_reg_type(devinfo, inst) == BRW_HW_REG_TYPE_F &&
- brw_inst_dst_reg_type(devinfo, inst) != GEN7_HW_REG_NON_IMM_TYPE_DF) {
- brw_inst_set_src0_reg_type(devinfo, inst, BRW_HW_REG_IMM_TYPE_VF);
- }
-
- /* There are no mappings for dst:d | i:d, so if the immediate is suitable
- * set the types to :UD so the instruction can be compacted.
- */
- if (is_compactable_immediate(brw_inst_imm_ud(devinfo, inst)) &&
- brw_inst_cond_modifier(devinfo, inst) == BRW_CONDITIONAL_NONE &&
- brw_inst_src0_reg_type(devinfo, inst) == BRW_HW_REG_TYPE_D &&
- brw_inst_dst_reg_type(devinfo, inst) == BRW_HW_REG_TYPE_D) {
- brw_inst_set_src0_reg_type(devinfo, inst, BRW_HW_REG_TYPE_UD);
- brw_inst_set_dst_reg_type(devinfo, inst, BRW_HW_REG_TYPE_UD);
+ brw_inst_set_src1_reg_type(devinfo, inst,
+ brw_inst_src0_reg_type(devinfo, inst));
}
} else {
if (reg.address_mode == BRW_ADDRESS_DIRECT) {
--
2.13.0
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