From 1e299ff828e808cbb1d92d9fedd528a3a8a3609e Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Wed, 1 Apr 2009 13:36:48 -0600 Subject: i965: another checkpoint commit of new constant buffer support Everything is in place now for using a true constant buffer for GLSL fragment shaders. Still some bugs to find though. --- src/mesa/drivers/dri/i965/brw_wm.h | 8 ++ src/mesa/drivers/dri/i965/brw_wm_glsl.c | 172 ++++++++++++++++++++------------ 2 files changed, 115 insertions(+), 65 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_wm.h b/src/mesa/drivers/dri/i965/brw_wm.h index 98c22121ec..d0ab3bdc65 100644 --- a/src/mesa/drivers/dri/i965/brw_wm.h +++ b/src/mesa/drivers/dri/i965/brw_wm.h @@ -253,6 +253,14 @@ struct brw_wm_compile { GLuint tmp_index; GLuint tmp_max; GLuint subroutines[BRW_WM_MAX_SUBROUTINE]; + + /** using a real constant buffer? */ + GLboolean use_const_buffer; + /** we may need up to 3 constants per instruction (if use_const_buffer) */ + struct { + GLint index; + struct brw_reg reg; + } current_const[3]; }; diff --git a/src/mesa/drivers/dri/i965/brw_wm_glsl.c b/src/mesa/drivers/dri/i965/brw_wm_glsl.c index 41db3a805b..01d1f7f0c2 100644 --- a/src/mesa/drivers/dri/i965/brw_wm_glsl.c +++ b/src/mesa/drivers/dri/i965/brw_wm_glsl.c @@ -193,7 +193,19 @@ static void prealloc_reg(struct brw_wm_compile *c) { const int nr_params = c->fp->program.Base.Parameters->NumParameters; - if (1 /* XXX threshold: nr_params <= 8 */) { + /* use a real constant buffer, or just use a section of the GRF? */ + c->use_const_buffer = GL_FALSE; /* (nr_params > 8);*/ + /*printf("USE CONST BUFFER? %d\n", c->use_const_buffer);*/ + + if (c->use_const_buffer) { + /* We'll use a real constant buffer and fetch constants from + * it with a dataport read message. + */ + + /* number of float constants in CURBE */ + c->prog_data.nr_params = 0; + } + else { const struct gl_program_parameter_list *plist = c->fp->program.Base.Parameters; int index = 0; @@ -217,16 +229,6 @@ static void prealloc_reg(struct brw_wm_compile *c) c->nr_creg = 2 * ((4 * nr_params + 15) / 16); c->reg_index += c->nr_creg; } - else { - /* number of float constants in CURBE */ - c->prog_data.nr_params = 0; - - /* When there's a lot of FP constanst we'll store them in a - * texture-like buffer instead of using the CURBE buffer. - * This means we won't use GRF registers for constants and we'll - * have to fetch constants with a dataport read. - */ - } } /* fragment shader inputs */ @@ -247,6 +249,49 @@ static void prealloc_reg(struct brw_wm_compile *c) c->reg_index++; c->stack = brw_uw16_reg(BRW_GENERAL_REGISTER_FILE, c->reg_index, 0); c->reg_index += 2; + + /* An instruction may reference up to three constants. + * They'll be found in these registers. + * XXX alloc these on demand! + */ + if (c->use_const_buffer) { + c->current_const[0].reg = alloc_tmp(c); + c->current_const[1].reg = alloc_tmp(c); + c->current_const[2].reg = alloc_tmp(c); + } + /*printf("AFTER PRE_ALLOC, reg_index = %d\n", c->reg_index);*/ +} + + +/** + * Check if any of the instruction's src registers are constants, uniforms, + * or statevars. If so, fetch any constants that we don't already have in + * the three GRF slots. + */ +static void fetch_constants(struct brw_wm_compile *c, + const struct prog_instruction *inst) +{ + struct brw_compile *p = &c->func; + GLuint i; + + /* loop over instruction src regs */ + for (i = 0; i < 3; i++) { + const struct prog_src_register *src = &inst->SrcReg[i]; + if (src->File == PROGRAM_STATE_VAR || + src->File == PROGRAM_UNIFORM) { + if (c->current_const[i].index != src->Index) { + /* need to fetch the constant now */ + brw_dp_READ_4(p, + c->current_const[i].reg, /* writeback dest */ + 1, /* msg_reg */ + src->RelAddr, /* relative indexing? */ + 16 * src->Index, /* byte offset */ + BRW_WM_MAX_SURF - 1 /* binding table index */ + ); + c->current_const[i].index = src->Index; + } + } + } } @@ -263,6 +308,43 @@ static struct brw_reg get_dst_reg(struct brw_wm_compile *c, } +static struct brw_reg +get_src_reg_const(struct brw_wm_compile *c, + const struct prog_instruction *inst, + GLuint srcRegIndex, GLuint component) +{ + /* We should have already fetched the constant from the constant + * buffer in fetch_constants(). Now we just have to return a + * register description that extracts the needed component and + * smears it across all eight vector components. + */ + const struct prog_src_register *src = &inst->SrcReg[srcRegIndex]; + struct brw_reg const_reg; + + assert(srcRegIndex < 3); + assert(c->current_const[srcRegIndex].index != -1); + const_reg = c->current_const[srcRegIndex].reg; + + /* + printf("get const reg %d in slot %d, comp %d\n", + c->current_const[srcRegIndex].index, + srcRegIndex, + component); + */ + + /* extract desired float from the const_reg, and smear */ + const_reg = stride(const_reg, 0, 1, 0); + const_reg.subnr = component * 4; + + if (src->NegateBase) + const_reg = negate(const_reg); + if (src->Abs) + const_reg = brw_abs(const_reg); + + return const_reg; +} + + /** * Convert Mesa src register to brw register. */ @@ -274,8 +356,16 @@ static struct brw_reg get_src_reg(struct brw_wm_compile *c, const GLuint nr = 1; const GLuint component = GET_SWZ(src->Swizzle, channel); - return get_reg(c, src->File, src->Index, component, nr, - src->NegateBase, src->Abs); + if (c->use_const_buffer && + (src->File == PROGRAM_STATE_VAR || + src->File == PROGRAM_UNIFORM)) { + return get_src_reg_const(c, inst, srcRegIndex, component); + } + else { + /* other type of source register */ + return get_reg(c, src->File, src->Index, component, nr, + src->NegateBase, src->Abs); + } } @@ -2473,48 +2563,6 @@ static void emit_tex(struct brw_wm_compile *c, } -static void emit_get_constant(struct brw_context *brw, - struct brw_wm_compile *c, - struct prog_instruction *inst, - GLuint constIndex) -{ - struct brw_compile *p = &c->func; - struct brw_reg dst[4]; - GLuint i; - const int mark = mark_tmps( c ); - struct brw_reg writeback_reg[4]; - - /* XXX only need 1 temp reg??? */ - for (i = 0; i < 4; i++) { - writeback_reg[i] = alloc_tmp(c); - } - - for (i = 0; i < 4; i++) { - dst[i] = get_dst_reg(c, inst, i); - } - - /* Get float[4] vector from constant buffer */ - brw_dp_READ_4(p, - writeback_reg[0], /* first writeback dest */ - 1, /* msg_reg */ - GL_FALSE, /* rel addr? */ - 16 * constIndex, /* byte offset */ - BRW_WM_MAX_SURF - 1 /* surface, binding table index */ - ); - - /* Extract the four channel values, smear across dest registers */ - for (i = 0; i < 4; i++) { - /* extract 1 float from the writeback reg */ - struct brw_reg new_src = stride(writeback_reg[0], 0, 1, 0); - new_src.subnr = i * 4; - /* and smear it into the dest register */ - brw_MOV(p, dst[i], new_src); - } - - release_tmps( c, mark ); -} - - /** * Resolve subroutine calls after code emit is done. */ @@ -2546,6 +2594,10 @@ static void brw_wm_emit_glsl(struct brw_context *brw, struct brw_wm_compile *c) else brw_set_conditionalmod(p, BRW_CONDITIONAL_NONE); + /* fetch any constants that this instruction needs */ + if (c->use_const_buffer) + fetch_constants(c, inst); + switch (inst->Opcode) { case WM_PIXELXY: emit_pixel_xy(c, inst); @@ -2599,17 +2651,7 @@ static void brw_wm_emit_glsl(struct brw_context *brw, struct brw_wm_compile *c) emit_trunc(c, inst); break; case OPCODE_MOV: -#if 0 - /* test hook for new constant buffer code */ - if (inst->SrcReg[0].File == PROGRAM_UNIFORM) { - emit_get_constant(brw, c, inst, inst->SrcReg[0].Index); - } - else { - emit_mov(c, inst); - } -#else emit_mov(c, inst); -#endif break; case OPCODE_DP3: emit_dp3(c, inst); -- cgit v1.2.3