r600g: Implement spilling of temp arrays (v2)
authorGlenn Kennard <glenn.kennard@gmail.com>
Sun, 5 Mar 2017 17:26:54 +0000 (18:26 +0100)
committerDave Airlie <airlied@redhat.com>
Thu, 8 Feb 2018 23:53:26 +0000 (09:53 +1000)
Pessimistically spills arrays if GPR limit is exceeded.

v2: fix r600 support [airlied]

Signed-off-by: Glenn Kennard <glenn.kennard@gmail.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
src/gallium/drivers/r600/r600_asm.c
src/gallium/drivers/r600/r600_asm.h
src/gallium/drivers/r600/r600_shader.c

index 7a4dddb7b6cb780a6d04de233e1741632918dc73..fdccae8c04c748521bd0cda36e8a11d5a5f80215 100644 (file)
@@ -240,6 +240,16 @@ int r600_bytecode_add_pending_output(struct r600_bytecode *bc,
        return 0;
 }
 
+void r600_bytecode_need_wait_ack(struct r600_bytecode *bc, boolean need_wait_ack)
+{
+       bc->need_wait_ack = need_wait_ack;
+}
+
+boolean r600_bytecode_get_need_wait_ack(struct r600_bytecode *bc)
+{
+       return bc->need_wait_ack;
+}
+
 /* alu instructions that can ony exits once per group */
 static int is_alu_once_inst(struct r600_bytecode_alu *alu)
 {
@@ -1511,6 +1521,13 @@ int r600_bytecode_add_gds(struct r600_bytecode *bc, const struct r600_bytecode_g
 int r600_bytecode_add_cfinst(struct r600_bytecode *bc, unsigned op)
 {
        int r;
+
+       /* Emit WAIT_ACK before control flow to ensure pending writes are always acked. */
+       if (op != CF_OP_MEM_SCRATCH && bc->need_wait_ack) {
+               bc->need_wait_ack = false;
+               r = r600_bytecode_add_cfinst(bc, CF_OP_WAIT_ACK);
+       }
+
        r = r600_bytecode_add_cf(bc);
        if (r)
                return r;
index 93ac717fb8f9b6eb9edf56a1d718a80e4f517f03..5841044bf819103d6a91e07443475470361ad3e5 100644 (file)
@@ -276,6 +276,7 @@ struct r600_bytecode {
        struct r600_isa* isa;
        struct r600_bytecode_output pending_outputs[5];
        int n_pending_outputs;
+       boolean                 need_wait_ack; /* emit a pending WAIT_ACK prior to control flow */
 };
 
 /* eg_asm.c */
@@ -304,6 +305,8 @@ int r600_bytecode_add_output(struct r600_bytecode *bc,
                const struct r600_bytecode_output *output);
 int r600_bytecode_add_pending_output(struct r600_bytecode *bc,
                const struct r600_bytecode_output *output);
+void r600_bytecode_need_wait_ack(struct r600_bytecode *bc, boolean needed);
+boolean r600_bytecode_get_need_wait_ack(struct r600_bytecode *bc);
 int r600_bytecode_build(struct r600_bytecode *bc);
 int r600_bytecode_add_cf(struct r600_bytecode *bc);
 int r600_bytecode_add_cfinst(struct r600_bytecode *bc,
index 903a66302632f38161324b112778b8045a287468..4141e864308085e61dd5bb42a9accd058aa04c1c 100644 (file)
@@ -165,7 +165,7 @@ int r600_pipe_shader_create(struct pipe_context *ctx,
        bool dump = r600_can_dump_shader(&rctx->screen->b,
                                         tgsi_get_processor_type(sel->tokens));
        unsigned use_sb = !(rctx->screen->b.debug_flags & DBG_NO_SB);
-       unsigned sb_disasm = use_sb || (rctx->screen->b.debug_flags & DBG_SB_DISASM);
+       unsigned sb_disasm;
        unsigned export_shader;
 
        shader->shader.bc.isa = rctx->isa;
@@ -208,6 +208,7 @@ int r600_pipe_shader_create(struct pipe_context *ctx,
                }
        }
 
+       sb_disasm = use_sb || (rctx->screen->b.debug_flags & DBG_SB_DISASM);
        if (dump && !sb_disasm) {
                fprintf(stderr, "--------------------------------------------------------------\n");
                r600_bytecode_disasm(&shader->shader.bc);
@@ -325,6 +326,9 @@ struct eg_interp {
 
 struct r600_shader_ctx {
        struct tgsi_shader_info                 info;
+       struct tgsi_array_info                  *array_infos;
+       /* flag for each tgsi temp array if its been spilled or not */
+       bool                                    *spilled_arrays;
        struct tgsi_parse_context               parse;
        const struct tgsi_token                 *tokens;
        unsigned                                type;
@@ -861,6 +865,95 @@ static int tgsi_barrier(struct r600_shader_ctx *ctx)
        return 0;
 }
 
+static void choose_spill_arrays(struct r600_shader_ctx *ctx, int *regno, unsigned *scratch_space_needed)
+{
+       // pick largest array and spill it, repeat until the number of temps is under limit or we run out of arrays
+       unsigned n = ctx->info.array_max[TGSI_FILE_TEMPORARY];
+       unsigned narrays_left = n;
+       bool *spilled = ctx->spilled_arrays; // assumed calloc:ed
+
+       *scratch_space_needed = 0;
+       while (*regno > 124 && narrays_left) {
+               unsigned i;
+               unsigned largest = 0;
+               unsigned largest_index = 0;
+
+               for (i = 0; i < n; i++) {
+                       unsigned size = ctx->array_infos[i].range.Last - ctx->array_infos[i].range.First + 1;
+                       if (!spilled[i] && size > largest) {
+                               largest = size;
+                               largest_index = i;
+                       }
+               }
+
+               spilled[largest_index] = true;
+               *regno -= largest;
+               *scratch_space_needed += largest;
+
+               narrays_left --;
+       }
+
+       if (narrays_left == 0) {
+               ctx->info.indirect_files &= ~(1 << TGSI_FILE_TEMPORARY);
+       }
+}
+
+/* Take spilled temp arrays into account when translating tgsi register
+ * indexes into r600 gprs if spilled is false, or scratch array offset if
+ * spilled is true */
+static int map_tgsi_reg_index_to_r600_gpr(struct r600_shader_ctx *ctx, unsigned tgsi_reg_index, bool *spilled)
+{
+       unsigned i;
+       unsigned spilled_size = 0;
+
+       for (i = 0; i < ctx->info.array_max[TGSI_FILE_TEMPORARY]; i++) {
+               if (tgsi_reg_index >= ctx->array_infos[i].range.First && tgsi_reg_index <= ctx->array_infos[i].range.Last) {
+                       if (ctx->spilled_arrays[i]) {
+                               /* vec4 index into spilled scratch memory */
+                               *spilled = true;
+                               return tgsi_reg_index - ctx->array_infos[i].range.First + spilled_size;
+                       }
+                       else {
+                               /* regular GPR array */
+                               *spilled = false;
+                               return tgsi_reg_index - spilled_size + ctx->file_offset[TGSI_FILE_TEMPORARY];
+                       }
+               }
+
+               if (ctx->spilled_arrays[i]) {
+                       spilled_size += ctx->array_infos[i].range.Last - ctx->array_infos[i].range.First + 1;
+               }
+       }
+
+       /* regular GPR index, minus the holes from spilled arrays */
+       *spilled = false;
+
+       return tgsi_reg_index - spilled_size + ctx->file_offset[TGSI_FILE_TEMPORARY];
+}
+
+/* look up spill area base offset and array size for a spilled temp array */
+static void get_spilled_array_base_and_size(struct r600_shader_ctx *ctx, unsigned tgsi_reg_index,
+       unsigned *array_base, unsigned *array_size)
+{
+       unsigned i;
+       unsigned offset = 0;
+
+       for (i = 0; i < ctx->info.array_max[TGSI_FILE_TEMPORARY]; i++) {
+               if (ctx->spilled_arrays[i]) {
+                       unsigned size = ctx->array_infos[i].range.Last - ctx->array_infos[i].range.First + 1;
+
+                       if (tgsi_reg_index >= ctx->array_infos[i].range.First && tgsi_reg_index <= ctx->array_infos[i].range.Last) {
+                               *array_base = offset;
+                               *array_size = size - 1; /* hw counts from 1 */
+
+                               return;
+                       }
+
+                       offset += size;
+               }
+       }
+}
+
 static int tgsi_declaration(struct r600_shader_ctx *ctx)
 {
        struct tgsi_full_declaration *d = &ctx->parse.FullToken.FullDeclaration;
@@ -965,10 +1058,15 @@ static int tgsi_declaration(struct r600_shader_ctx *ctx)
        case TGSI_FILE_TEMPORARY:
                if (ctx->info.indirect_files & (1 << TGSI_FILE_TEMPORARY)) {
                        if (d->Array.ArrayID) {
-                               r600_add_gpr_array(ctx->shader,
-                                              ctx->file_offset[TGSI_FILE_TEMPORARY] +
-                                                                  d->Range.First,
-                                              d->Range.Last - d->Range.First + 1, 0x0F);
+                               bool spilled;
+                               unsigned idx = map_tgsi_reg_index_to_r600_gpr(ctx,
+                                       d->Range.First,
+                                       &spilled);
+
+                               if (!spilled) {
+                                       r600_add_gpr_array(ctx->shader, idx,
+                                               d->Range.Last - d->Range.First + 1, 0x0F);
+                               }
                        }
                }
                break;
@@ -1408,6 +1506,95 @@ static void tgsi_src(struct r600_shader_ctx *ctx,
        r600_src->neg = tgsi_src->Register.Negate;
        r600_src->abs = tgsi_src->Register.Absolute;
 
+       if (tgsi_src->Register.File == TGSI_FILE_TEMPORARY) {
+               bool spilled;
+               unsigned idx;
+
+               idx = map_tgsi_reg_index_to_r600_gpr(ctx, tgsi_src->Register.Index, &spilled);
+
+               if (spilled) {
+                       int reg = r600_get_temp(ctx);
+                       int r;
+
+                       r600_src->sel = reg;
+
+                       if (ctx->bc->chip_class < R700) {
+                               struct r600_bytecode_output cf;
+
+                               memset(&cf, 0, sizeof(struct r600_bytecode_output));
+                               cf.op = CF_OP_MEM_SCRATCH;
+                               cf.elem_size = 3;
+                               cf.gpr = reg;
+                               cf.comp_mask = 0xF;
+                               cf.swizzle_x = 0;
+                               cf.swizzle_y = 1;
+                               cf.swizzle_z = 2;
+                               cf.swizzle_w = 3;
+                               cf.burst_count = 1;
+
+                               get_spilled_array_base_and_size(ctx, tgsi_src->Register.Index,
+                                       &cf.array_base, &cf.array_size);
+
+                               if (tgsi_src->Register.Indirect) {
+                                       cf.type = V_SQ_CF_ALLOC_EXPORT_WORD0_SQ_EXPORT_READ_IND;
+                                       cf.index_gpr = ctx->bc->ar_reg;
+                               }
+                               else {
+                                       cf.type = V_SQ_CF_ALLOC_EXPORT_WORD0_SQ_EXPORT_READ;
+                                       cf.array_base += idx;
+                                       cf.array_size = 0;
+                               }
+
+                               r = r600_bytecode_add_output(ctx->bc, &cf);
+                       }
+                       else {
+                               struct r600_bytecode_vtx vtx;
+
+                               if (r600_bytecode_get_need_wait_ack(ctx->bc)) {
+                                       r600_bytecode_need_wait_ack(ctx->bc, false);
+                                       r = r600_bytecode_add_cfinst(ctx->bc, CF_OP_WAIT_ACK);
+                               }
+
+                               memset(&vtx, 0, sizeof(struct r600_bytecode_vtx));
+                               vtx.op = FETCH_OP_READ_SCRATCH;
+                               vtx.dst_gpr = reg;
+                               vtx.uncached = 1; // Must bypass cache since prior spill written in same invocation
+                               vtx.elem_size = 3;
+                               vtx.data_format = FMT_32_32_32_32;
+                               vtx.num_format_all = V_038010_SQ_NUM_FORMAT_INT;
+                               vtx.dst_sel_x = tgsi_src->Register.SwizzleX;
+                               vtx.dst_sel_y = tgsi_src->Register.SwizzleY;
+                               vtx.dst_sel_z = tgsi_src->Register.SwizzleZ;
+                               vtx.dst_sel_w = tgsi_src->Register.SwizzleW;
+
+                               get_spilled_array_base_and_size(ctx, tgsi_src->Register.Index,
+                                       &vtx.array_base, &vtx.array_size);
+
+                               if (tgsi_src->Register.Indirect) {
+                                       vtx.indexed = 1;
+                                       vtx.src_gpr = ctx->bc->ar_reg;
+                               }
+                               else {
+                                       vtx.array_base += idx;
+                                       vtx.array_size = 0;
+                               }
+
+                               r = r600_bytecode_add_vtx(ctx->bc, &vtx);
+                       }
+
+                       if (r)
+                               return;
+               }
+               else {
+                       if (tgsi_src->Register.Indirect)
+                               r600_src->rel = V_SQ_REL_RELATIVE;
+
+                       r600_src->sel = idx;
+               }
+
+               return;
+       }
+
        if (tgsi_src->Register.File == TGSI_FILE_IMMEDIATE) {
                int index;
                if ((tgsi_src->Register.SwizzleX == tgsi_src->Register.SwizzleY) &&
@@ -3173,6 +3360,11 @@ static int r600_shader_from_tgsi(struct r600_context *rctx,
        tgsi_scan_shader(tokens, &ctx.info);
        shader->indirect_files = ctx.info.indirect_files;
 
+       int narrays = ctx.info.array_max[TGSI_FILE_TEMPORARY];
+       ctx.array_infos = calloc(narrays, sizeof(*ctx.array_infos));
+       ctx.spilled_arrays = calloc(narrays, sizeof(bool));
+       tgsi_scan_arrays(tokens, TGSI_FILE_TEMPORARY, narrays, ctx.array_infos);
+
        shader->uses_helper_invocation = false;
        shader->uses_doubles = ctx.info.uses_doubles;
        shader->uses_atomics = ctx.info.file_mask[TGSI_FILE_HW_ATOMIC];
@@ -3342,11 +3534,17 @@ static int r600_shader_from_tgsi(struct r600_context *rctx,
        /* Outside the GPR range. This will be translated to one of the
         * kcache banks later. */
        ctx.file_offset[TGSI_FILE_CONSTANT] = 512;
-
        ctx.file_offset[TGSI_FILE_IMMEDIATE] = V_SQ_ALU_SRC_LITERAL;
 
+       pipeshader->scratch_space_needed = 0;
        int regno = ctx.file_offset[TGSI_FILE_TEMPORARY] +
                        ctx.info.file_max[TGSI_FILE_TEMPORARY];
+       if (regno > 124) {
+               choose_spill_arrays(&ctx, &regno, &pipeshader->scratch_space_needed);
+               shader->indirect_files = ctx.info.indirect_files;
+       }
+       shader->needs_scratch_space = pipeshader->scratch_space_needed != 0;
+
        ctx.bc->ar_reg = ++regno;
        ctx.bc->index_reg[0] = ++regno;
        ctx.bc->index_reg[1] = ++regno;
@@ -4061,10 +4259,14 @@ static int r600_shader_from_tgsi(struct r600_context *rctx,
                        return r;
        }
 
+       free(ctx.spilled_arrays);
+       free(ctx.array_infos);
        free(ctx.literals);
        tgsi_parse_free(&ctx.parse);
        return 0;
 out_err:
+       free(ctx.spilled_arrays);
+       free(ctx.array_infos);
        free(ctx.literals);
        tgsi_parse_free(&ctx.parse);
        return r;
@@ -4116,8 +4318,70 @@ static void tgsi_dst(struct r600_shader_ctx *ctx,
 {
        struct tgsi_full_instruction *inst = &ctx->parse.FullToken.FullInstruction;
 
-       r600_dst->sel = tgsi_dst->Register.Index;
-       r600_dst->sel += ctx->file_offset[tgsi_dst->Register.File];
+       if (tgsi_dst->Register.File == TGSI_FILE_TEMPORARY) {
+               bool spilled;
+               unsigned idx;
+
+               idx = map_tgsi_reg_index_to_r600_gpr(ctx, tgsi_dst->Register.Index, &spilled);
+
+               if (spilled) {
+                       struct r600_bytecode_output cf;
+                       int reg = r600_get_temp(ctx);
+                       int r;
+
+                       r600_dst->sel = reg;
+                       r600_dst->chan = swizzle;
+                       r600_dst->write = 1;
+                       if (inst->Instruction.Saturate) {
+                               r600_dst->clamp = 1;
+                       }
+
+                       // needs to be added after op using tgsi_dst
+                       memset(&cf, 0, sizeof(struct r600_bytecode_output));
+                       cf.op = CF_OP_MEM_SCRATCH;
+                       cf.elem_size = 3;
+                       cf.gpr = reg;
+                       cf.type = V_SQ_CF_ALLOC_EXPORT_WORD0_SQ_EXPORT_WRITE;
+                       cf.mark = 1;
+                       cf.comp_mask = inst->Dst[0].Register.WriteMask;
+                       cf.swizzle_x = 0;
+                       cf.swizzle_y = 1;
+                       cf.swizzle_z = 2;
+                       cf.swizzle_w = 3;
+                       cf.burst_count = 1;
+
+                       get_spilled_array_base_and_size(ctx, tgsi_dst->Register.Index,
+                               &cf.array_base, &cf.array_size);
+
+                       if (tgsi_dst->Register.Indirect) {
+                               if (ctx->bc->chip_class < R700)
+                                       cf.type = V_SQ_CF_ALLOC_EXPORT_WORD0_SQ_EXPORT_WRITE_IND;
+                               else
+                                       cf.type = 3; // V_SQ_CF_ALLOC_EXPORT_WORD0_SQ_EXPORT_WRITE_IND_ACK;
+                               cf.index_gpr = ctx->bc->ar_reg;
+                       }
+                       else {
+                               cf.array_base += idx;
+                               cf.array_size = 0;
+                       }
+
+                       r = r600_bytecode_add_pending_output(ctx->bc, &cf);
+                       if (r)
+                               return;
+
+                       if (ctx->bc->chip_class >= R700)
+                               r600_bytecode_need_wait_ack(ctx->bc, true);
+
+                       return;
+               }
+               else {
+                       r600_dst->sel = idx;
+               }
+       }
+       else {
+               r600_dst->sel = tgsi_dst->Register.Index;
+               r600_dst->sel += ctx->file_offset[tgsi_dst->Register.File];
+       }
        r600_dst->chan = swizzle;
        r600_dst->write = 1;
        if (inst->Instruction.Saturate) {