From c51c822ee02cb47ddba46da668577d51b7c02831 Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Fri, 13 Feb 2009 17:17:52 -0700 Subject: [PATCH] i965: rewrite the code for handling shader subroutine calls Previously, the prog_instruction::Data field was used to map original Mesa instructions to brw instructions in order to resolve subroutine calls. This was a rather tangled mess. Plus it's an obstacle to implementing dynamic allocation/growing of the instruction buffer (it's still a fixed size). Mesa's GLSL compiler emits a label for each subroutine and CAL instruction. Now we use those labels to patch the subroutine calls after code generation has been done. We just keep a list of all CAL instructions that needs patching and a list of all subroutine labels. It's a simple matter to resolve them. This also consolidates some redundant post-emit code between brw_vs_emit.c and brw_wm_glsl.c and removes some loops that cleared the prog_instruction::Data fields at the end. Plus, a bunch of new comments. --- src/mesa/drivers/dri/i965/brw_eu.c | 123 ++++++++++++++++++++++++++++++++ src/mesa/drivers/dri/i965/brw_eu.h | 18 +++++ src/mesa/drivers/dri/i965/brw_vs_emit.c | 71 +++++++++--------- src/mesa/drivers/dri/i965/brw_wm.h | 2 + src/mesa/drivers/dri/i965/brw_wm_fp.c | 1 - src/mesa/drivers/dri/i965/brw_wm_glsl.c | 36 +++------- 6 files changed, 187 insertions(+), 64 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_eu.c b/src/mesa/drivers/dri/i965/brw_eu.c index b3ae4ee..c53efba 100644 --- a/src/mesa/drivers/dri/i965/brw_eu.c +++ b/src/mesa/drivers/dri/i965/brw_eu.c @@ -129,3 +129,126 @@ const GLuint *brw_get_program( struct brw_compile *p, return (const GLuint *)p->store; } + + +/** + * Subroutine calls require special attention. + * Mesa instructions may be expanded into multiple hardware instructions + * so the prog_instruction::BranchTarget field can't be used as an index + * into the hardware instructions. + * + * The BranchTarget field isn't needed, however. Mesa's GLSL compiler + * emits CAL and BGNSUB instructions with labels that can be used to map + * subroutine calls to actual subroutine code blocks. + * + * The structures and function here implement patching of CAL instructions + * so they jump to the right subroutine code... + */ + + +/** + * For each OPCODE_BGNSUB we create one of these. + */ +struct brw_glsl_label +{ + const char *name; /**< the label string */ + GLuint position; /**< the position of the brw instruction for this label */ + struct brw_glsl_label *next; /**< next in linked list */ +}; + + +/** + * For each OPCODE_CAL we create one of these. + */ +struct brw_glsl_call +{ + GLuint call_inst_pos; /**< location of the CAL instruction */ + const char *sub_name; /**< name of subroutine to call */ + struct brw_glsl_call *next; /**< next in linked list */ +}; + + +/** + * Called for each OPCODE_BGNSUB. + */ +void +brw_save_label(struct brw_compile *c, const char *name, GLuint position) +{ + struct brw_glsl_label *label = CALLOC_STRUCT(brw_glsl_label); + label->name = name; + label->position = position; + label->next = c->first_label; + c->first_label = label; +} + + +/** + * Called for each OPCODE_CAL. + */ +void +brw_save_call(struct brw_compile *c, const char *name, GLuint call_pos) +{ + struct brw_glsl_call *call = CALLOC_STRUCT(brw_glsl_call); + call->call_inst_pos = call_pos; + call->sub_name = name; + call->next = c->first_call; + c->first_call = call; +} + + +/** + * Lookup a label, return label's position/offset. + */ +static GLuint +brw_lookup_label(struct brw_compile *c, const char *name) +{ + const struct brw_glsl_label *label; + for (label = c->first_label; label; label = label->next) { + if (strcmp(name, label->name) == 0) { + return label->position; + } + } + abort(); /* should never happen */ + return ~0; +} + + +/** + * When we're done generating code, this function is called to resolve + * subroutine calls. + */ +void +brw_resolve_cals(struct brw_compile *c) +{ + const struct brw_glsl_call *call; + + for (call = c->first_call; call; call = call->next) { + const GLuint sub_loc = brw_lookup_label(c, call->sub_name); + struct brw_instruction *brw_call_inst = &c->store[call->call_inst_pos]; + struct brw_instruction *brw_sub_inst = &c->store[sub_loc]; + GLint offset = brw_sub_inst - brw_call_inst; + + /* patch brw_inst1 to point to brw_inst2 */ + brw_set_src1(brw_call_inst, brw_imm_d(offset * 16)); + } + + /* free linked list of calls */ + { + struct brw_glsl_call *call, *next; + for (call = c->first_call; call; call = next) { + next = call->next; + _mesa_free(call); + } + c->first_call = NULL; + } + + /* free linked list of labels */ + { + struct brw_glsl_label *label, *next; + for (label = c->first_label; label; label = next) { + next = label->next; + _mesa_free(label); + } + c->first_label = NULL; + } +} diff --git a/src/mesa/drivers/dri/i965/brw_eu.h b/src/mesa/drivers/dri/i965/brw_eu.h index 9e2b39a..b36a197 100644 --- a/src/mesa/drivers/dri/i965/brw_eu.h +++ b/src/mesa/drivers/dri/i965/brw_eu.h @@ -91,6 +91,11 @@ struct brw_indirect { }; +struct brw_glsl_label; +struct brw_glsl_call; + + + #define BRW_EU_MAX_INSN_STACK 5 #define BRW_EU_MAX_INSN 1200 @@ -106,9 +111,22 @@ struct brw_compile { GLuint flag_value; GLboolean single_program_flow; struct brw_context *brw; + + struct brw_glsl_label *first_label; /**< linked list of labels */ + struct brw_glsl_call *first_call; /**< linked list of CALs */ }; +void +brw_save_label(struct brw_compile *c, const char *name, GLuint position); + +void +brw_save_call(struct brw_compile *c, const char *name, GLuint call_pos); + +void +brw_resolve_cals(struct brw_compile *c); + + static INLINE int type_sz( GLuint type ) { diff --git a/src/mesa/drivers/dri/i965/brw_vs_emit.c b/src/mesa/drivers/dri/i965/brw_vs_emit.c index a1328f6..235f826 100644 --- a/src/mesa/drivers/dri/i965/brw_vs_emit.c +++ b/src/mesa/drivers/dri/i965/brw_vs_emit.c @@ -954,36 +954,27 @@ static void emit_vertex_write( struct brw_vs_compile *c) } +/** + * Called after code generation to resolve subroutine calls and the + * END instruction. + * \param end_inst points to brw code for END instruction + * \param last_inst points to last instruction emitted before vertex write + */ static void -post_vs_emit( struct brw_vs_compile *c, struct brw_instruction *end_inst ) +post_vs_emit( struct brw_vs_compile *c, + struct brw_instruction *end_inst, + struct brw_instruction *last_inst ) { - GLuint nr_insns = c->vp->program.Base.NumInstructions; - GLuint insn, target_insn; - struct prog_instruction *inst1, *inst2; - struct brw_instruction *brw_inst1, *brw_inst2; - int offset; - for (insn = 0; insn < nr_insns; insn++) { - inst1 = &c->vp->program.Base.Instructions[insn]; - brw_inst1 = inst1->Data; - switch (inst1->Opcode) { - case OPCODE_CAL: - case OPCODE_BRA: - target_insn = inst1->BranchTarget; - inst2 = &c->vp->program.Base.Instructions[target_insn]; - brw_inst2 = inst2->Data; - offset = brw_inst2 - brw_inst1; - brw_set_src1(brw_inst1, brw_imm_d(offset*16)); - break; - case OPCODE_END: - offset = end_inst - brw_inst1; - brw_set_src1(brw_inst1, brw_imm_d(offset*16)); - break; - default: - break; - } - } + GLint offset; + + brw_resolve_cals(&c->func); + + /* patch up the END code to jump past subroutines, etc */ + offset = last_inst - end_inst; + brw_set_src1(end_inst, brw_imm_d(offset * 16)); } + /* Emit the fragment program instructions here. */ void brw_vs_emit(struct brw_vs_compile *c ) @@ -992,7 +983,8 @@ void brw_vs_emit(struct brw_vs_compile *c ) struct brw_compile *p = &c->func; GLuint nr_insns = c->vp->program.Base.NumInstructions; GLuint insn, if_insn = 0; - struct brw_instruction *end_inst; + GLuint end_offset = 0; + struct brw_instruction *end_inst, *last_inst; struct brw_instruction *if_inst[MAX_IFSN]; struct brw_indirect stack_index = brw_indirect(0, 0); @@ -1035,7 +1027,6 @@ void brw_vs_emit(struct brw_vs_compile *c ) /* Get argument regs. SWZ is special and does this itself. */ - inst->Data = &p->store[p->nr_insn]; if (inst->Opcode != OPCODE_SWZ) for (i = 0; i < 3; i++) { struct prog_src_register *src = &inst->SrcReg[i]; @@ -1203,7 +1194,7 @@ void brw_vs_emit(struct brw_vs_compile *c ) brw_set_access_mode(p, BRW_ALIGN_16); brw_ADD(p, get_addr_reg(stack_index), get_addr_reg(stack_index), brw_imm_d(4)); - inst->Data = &p->store[p->nr_insn]; + brw_save_call(p, inst->Comment, p->nr_insn); brw_ADD(p, brw_ip_reg(), brw_ip_reg(), brw_imm_d(1*16)); break; case OPCODE_RET: @@ -1214,13 +1205,21 @@ void brw_vs_emit(struct brw_vs_compile *c ) brw_set_access_mode(p, BRW_ALIGN_16); break; case OPCODE_END: + end_offset = p->nr_insn; + /* this instruction will get patched later to jump past subroutine + * code, etc. + */ brw_ADD(p, brw_ip_reg(), brw_ip_reg(), brw_imm_d(1*16)); break; case OPCODE_PRINT: + /* no-op */ + break; case OPCODE_BGNSUB: + brw_save_label(p, inst->Comment, p->nr_insn); + break; case OPCODE_ENDSUB: - /* no-op instructions */ - break; + /* no-op */ + break; default: _mesa_problem(NULL, "Unsupported opcode %i (%s) in vertex shader", inst->Opcode, inst->Opcode < MAX_OPCODE ? @@ -1258,9 +1257,11 @@ void brw_vs_emit(struct brw_vs_compile *c ) release_tmps(c); } - end_inst = &p->store[p->nr_insn]; + end_inst = &p->store[end_offset]; + last_inst = &p->store[p->nr_insn]; + + /* The END instruction will be patched to jump to this code */ emit_vertex_write(c); - post_vs_emit(c, end_inst); - for (insn = 0; insn < nr_insns; insn++) - c->vp->program.Base.Instructions[insn].Data = NULL; + + post_vs_emit(c, end_inst, last_inst); } diff --git a/src/mesa/drivers/dri/i965/brw_wm.h b/src/mesa/drivers/dri/i965/brw_wm.h index 0f46a25..582031f 100644 --- a/src/mesa/drivers/dri/i965/brw_wm.h +++ b/src/mesa/drivers/dri/i965/brw_wm.h @@ -281,4 +281,6 @@ void brw_wm_lookup_iz( GLuint line_aa, GLboolean brw_wm_is_glsl(const struct gl_fragment_program *fp); void brw_wm_glsl_emit(struct brw_context *brw, struct brw_wm_compile *c); + + #endif diff --git a/src/mesa/drivers/dri/i965/brw_wm_fp.c b/src/mesa/drivers/dri/i965/brw_wm_fp.c index 0a44f8b..8b5ccdb 100644 --- a/src/mesa/drivers/dri/i965/brw_wm_fp.c +++ b/src/mesa/drivers/dri/i965/brw_wm_fp.c @@ -183,7 +183,6 @@ static struct prog_instruction *emit_insn(struct brw_wm_compile *c, { struct prog_instruction *inst = get_fp_inst(c); *inst = *inst0; - inst->Data = (void *)inst0; return inst; } diff --git a/src/mesa/drivers/dri/i965/brw_wm_glsl.c b/src/mesa/drivers/dri/i965/brw_wm_glsl.c index 0d3e2eb..d99aa37 100644 --- a/src/mesa/drivers/dri/i965/brw_wm_glsl.c +++ b/src/mesa/drivers/dri/i965/brw_wm_glsl.c @@ -2252,28 +2252,12 @@ static void emit_tex(struct brw_wm_compile *c, brw_MOV(p, dst[3], brw_imm_f(1.0)); } +/** + * Resolve subroutine calls after code emit is done. + */ static void post_wm_emit( struct brw_wm_compile *c ) { - GLuint nr_insns = c->fp->program.Base.NumInstructions; - GLuint insn, target_insn; - struct prog_instruction *inst1, *inst2; - struct brw_instruction *brw_inst1, *brw_inst2; - int offset; - for (insn = 0; insn < nr_insns; insn++) { - inst1 = &c->fp->program.Base.Instructions[insn]; - brw_inst1 = inst1->Data; - switch (inst1->Opcode) { - case OPCODE_CAL: - target_insn = inst1->BranchTarget; - inst2 = &c->fp->program.Base.Instructions[target_insn]; - brw_inst2 = inst2->Data; - offset = brw_inst2 - brw_inst1; - brw_set_src1(brw_inst1, brw_imm_d(offset*16)); - break; - default: - break; - } - } + brw_resolve_cals(&c->func); } static void brw_wm_emit_glsl(struct brw_context *brw, struct brw_wm_compile *c) @@ -2293,10 +2277,6 @@ static void brw_wm_emit_glsl(struct brw_context *brw, struct brw_wm_compile *c) for (i = 0; i < c->nr_fp_insns; i++) { struct prog_instruction *inst = &c->prog_instructions[i]; - struct prog_instruction *orig_inst; - - if ((orig_inst = inst->Data) != 0) - orig_inst->Data = current_insn(p); if (inst->CondUpdate) brw_set_conditionalmod(p, BRW_CONDITIONAL_NZ); @@ -2454,7 +2434,10 @@ static void brw_wm_emit_glsl(struct brw_context *brw, struct brw_wm_compile *c) brw_ENDIF(p, if_inst[--if_insn]); break; case OPCODE_BGNSUB: + brw_save_label(p, inst->Comment, p->nr_insn); + break; case OPCODE_ENDSUB: + /* no-op */ break; case OPCODE_CAL: brw_push_insn_state(p); @@ -2464,8 +2447,7 @@ static void brw_wm_emit_glsl(struct brw_context *brw, struct brw_wm_compile *c) brw_set_access_mode(p, BRW_ALIGN_16); brw_ADD(p, get_addr_reg(stack_index), get_addr_reg(stack_index), brw_imm_d(4)); - orig_inst = inst->Data; - orig_inst->Data = &p->store[p->nr_insn]; + brw_save_call(&c->func, inst->Comment, p->nr_insn); brw_ADD(p, brw_ip_reg(), brw_ip_reg(), brw_imm_d(1*16)); brw_pop_insn_state(p); break; @@ -2518,8 +2500,6 @@ static void brw_wm_emit_glsl(struct brw_context *brw, struct brw_wm_compile *c) brw_set_predicate_control(p, BRW_PREDICATE_NONE); } post_wm_emit(c); - for (i = 0; i < c->fp->program.Base.NumInstructions; i++) - c->fp->program.Base.Instructions[i].Data = NULL; } -- 2.7.4