From ecf85c7d750478e433e640897bb25a18069f14de Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Thu, 18 Mar 2010 11:18:01 -0600 Subject: [PATCH] gallivm: checkpoint WIP two-sided stencil test --- src/gallium/auxiliary/gallivm/lp_bld_depth.c | 221 ++++++++++++++++--- 1 file changed, 191 insertions(+), 30 deletions(-) diff --git a/src/gallium/auxiliary/gallivm/lp_bld_depth.c b/src/gallium/auxiliary/gallivm/lp_bld_depth.c index e4500e5aef1..49de5c94a3c 100644 --- a/src/gallium/auxiliary/gallivm/lp_bld_depth.c +++ b/src/gallium/auxiliary/gallivm/lp_bld_depth.c @@ -52,7 +52,14 @@ * Z31 Z32 Z41 Z42 Z33 Z34 Z43 Z44 ... * ... ... ... ... ... ... ... ... ... * - * FIXME: Code generate stencil test + * + * Stencil test: + * Two-sided stencil test is supported but probably not as efficient as + * it could be. Currently, we use if/then/else constructs to do the + * operations for front vs. back-facing polygons. We could probably do + * both the front and back arithmetic then use a Select() instruction to + * choose the result depending on polyon orientation. We'd have to + * measure performance both ways and see which is better. * * @author Jose Fonseca */ @@ -70,18 +77,28 @@ #include "lp_bld_swizzle.h" +/** Used to select fields from pipe_stencil_state */ +enum stencil_op { + S_FAIL_OP, + Z_FAIL_OP, + Z_PASS_OP +}; + + /** - * Do the stencil test comparison (compare fb Z values against ref value. - * \param stencilVals vector of stencil values from framebuffer + * Do the stencil test comparison (compare FB stencil values against ref value). + * This will be used twice when generating two-sided stencil code. + * \param stencil the front/back stencil state * \param stencilRef the stencil reference value, replicated as a vector - * \return mask of pass/fail values + * \param stencilVals vector of stencil values from framebuffer + * \return vector mask of pass/fail values (~0 or 0) */ static LLVMValueRef -lp_build_stencil_test(struct lp_build_context *bld, - const struct pipe_stencil_state *stencil, - LLVMValueRef stencilRef, - LLVMValueRef stencilVals) +lp_build_stencil_test_single(struct lp_build_context *bld, + const struct pipe_stencil_state *stencil, + LLVMValueRef stencilRef, + LLVMValueRef stencilVals) { const unsigned stencilMax = 255; /* XXX fix */ struct lp_type type = bld->type; @@ -103,24 +120,100 @@ lp_build_stencil_test(struct lp_build_context *bld, } +/** + * Do the one or two-sided stencil test comparison. + * \sa lp_build_stencil_test_single + * \param face an integer indicating front (+) or back (-) facing polygon. + * If NULL, assume front-facing. + */ +static LLVMValueRef +lp_build_stencil_test(struct lp_build_context *bld, + const struct pipe_stencil_state stencil[2], + LLVMValueRef stencilRefs[2], + LLVMValueRef stencilVals, + LLVMValueRef face) +{ + LLVMValueRef res; + + assert(stencil[0].enabled); + + if (stencil[1].enabled && face) { + /* do two-sided test */ + struct lp_build_flow_context *flow_ctx; + struct lp_build_if_state if_ctx; + LLVMValueRef front_facing; + LLVMValueRef zero = LLVMConstReal(LLVMFloatType(), 0.0); + LLVMValueRef result = NULL; + + flow_ctx = lp_build_flow_create(bld->builder); + lp_build_flow_scope_begin(flow_ctx); + + lp_build_flow_scope_declare(flow_ctx, &result); + + /* front_facing = face > 0.0 */ + front_facing = lp_build_cmp(bld, PIPE_FUNC_GREATER, face, zero); + + lp_build_if(&if_ctx, flow_ctx, bld->builder, front_facing); + { + result = lp_build_stencil_test_single(bld, &stencil[0], + stencilRefs[0], stencilVals); + } + lp_build_else(&if_ctx); + { + result = lp_build_stencil_test_single(bld, &stencil[1], + stencilRefs[1], stencilVals); + } + lp_build_endif(&if_ctx); + + lp_build_flow_scope_end(flow_ctx); + lp_build_flow_destroy(flow_ctx); + + res = result; + } + else { + /* do single-side test */ + res = lp_build_stencil_test_single(bld, &stencil[0], + stencilRefs[0], stencilVals); + } + + return res; +} + + /** * Apply the stencil operator (add/sub/keep/etc) to the given vector * of stencil values. * \return new stencil values vector */ static LLVMValueRef -lp_build_stencil_op(struct lp_build_context *bld, - const struct pipe_stencil_state *stencil, - unsigned stencil_op, - LLVMValueRef stencilRef, - LLVMValueRef stencilVals, - LLVMValueRef mask) +lp_build_stencil_op_single(struct lp_build_context *bld, + const struct pipe_stencil_state *stencil, + enum stencil_op op, + LLVMValueRef stencilRef, + LLVMValueRef stencilVals, + LLVMValueRef mask) { const unsigned stencilMax = 255; /* XXX fix */ struct lp_type type = bld->type; LLVMValueRef res; LLVMValueRef max = lp_build_const_int_vec(type, stencilMax); + unsigned stencil_op; + + switch (op) { + case S_FAIL_OP: + stencil_op = stencil->fail_op; + break; + case Z_FAIL_OP: + stencil_op = stencil->zfail_op; + break; + case Z_PASS_OP: + stencil_op = stencil->zpass_op; + break; + default: + assert(0 && "Invalid stencil_op mode"); + stencil_op = PIPE_STENCIL_OP_KEEP; + } switch (stencil_op) { case PIPE_STENCIL_OP_KEEP: @@ -173,6 +266,63 @@ lp_build_stencil_op(struct lp_build_context *bld, } +/** + * Do the one or two-sided stencil test op/update. + */ +static LLVMValueRef +lp_build_stencil_op(struct lp_build_context *bld, + const struct pipe_stencil_state stencil[2], + enum stencil_op op, + LLVMValueRef stencilRefs[2], + LLVMValueRef stencilVals, + LLVMValueRef mask, + LLVMValueRef face) + +{ + assert(stencil[0].enabled); + + if (stencil[1].enabled && face) { + /* do two-sided op */ + struct lp_build_flow_context *flow_ctx; + struct lp_build_if_state if_ctx; + LLVMValueRef front_facing; + LLVMValueRef zero = LLVMConstReal(LLVMFloatType(), 0.0); + LLVMValueRef result = NULL; + + flow_ctx = lp_build_flow_create(bld->builder); + lp_build_flow_scope_begin(flow_ctx); + + lp_build_flow_scope_declare(flow_ctx, &result); + + /* front_facing = face > 0.0 */ + front_facing = lp_build_cmp(bld, PIPE_FUNC_GREATER, face, zero); + + lp_build_if(&if_ctx, flow_ctx, bld->builder, front_facing); + { + result = lp_build_stencil_op_single(bld, &stencil[0], op, + stencilRefs[0], stencilVals, mask); + } + lp_build_else(&if_ctx); + { + result = lp_build_stencil_op_single(bld, &stencil[1], op, + stencilRefs[1], stencilVals, mask); + } + lp_build_endif(&if_ctx); + + lp_build_flow_scope_end(flow_ctx); + lp_build_flow_destroy(flow_ctx); + + return result; + } + else { + /* do single-sided op */ + return lp_build_stencil_op_single(bld, &stencil[0], op, + stencilRefs[0], stencilVals, mask); + } +} + + + /** * Return a type appropriate for depth/stencil testing. */ @@ -213,14 +363,19 @@ lp_depth_type(const struct util_format_description *format_desc, } +/** Get front/back-face stencil ref value */ static LLVMValueRef lp_build_get_stencil_ref(struct lp_build_context *bld, - struct lp_type type, LLVMValueRef stencil_refs_ptr) + struct lp_type type, LLVMValueRef stencil_refs_ptr, + unsigned face_index) { LLVMValueRef indexes[2], ptr, ref, ref_vec; - /* load 0th element of the array */ - indexes[0] = indexes[1] = LLVMConstInt(LLVMInt32Type(), 0, 0); + assert(face_index < 2); + + /* load [face_index] element of the array */ + indexes[0] = LLVMConstInt(LLVMInt32Type(), 0, 0); + indexes[1] = LLVMConstInt(LLVMInt32Type(), face_index, 0); ptr = LLVMBuildGEP(bld->builder, stencil_refs_ptr, indexes, 2, ""); ref = LLVMBuildLoad(bld->builder, ptr, ""); @@ -251,17 +406,19 @@ lp_build_depth_stencil_test(LLVMBuilderRef builder, struct lp_type type, const struct util_format_description *format_desc, struct lp_build_mask_context *mask, - LLVMValueRef stencil_refs, + LLVMValueRef stencil_refs_ptr, LLVMValueRef z_src, LLVMValueRef zs_dst_ptr) { struct lp_build_context bld; unsigned z_swizzle, s_swizzle; + LLVMValueRef stencil_refs[2]; LLVMValueRef zs_dst, z_dst = NULL; LLVMValueRef stencil_vals = NULL; LLVMValueRef z_bitmask = NULL, s_bitmask = NULL; LLVMValueRef z_pass = NULL, s_pass_mask = NULL; LLVMValueRef orig_mask = mask->value; + LLVMValueRef face = NULL; assert(depth->enabled || stencil[0].enabled); @@ -345,25 +502,29 @@ lp_build_depth_stencil_test(LLVMBuilderRef builder, lp_build_name(z_dst, "zsbuf.z"); - /* + printf("build depth %d stencil %d\n", depth->enabled, stencil[0].enabled); - */ + if (stencil[0].enabled) { /* Incoming stencil_refs is ptr to int8[2]. Get/convert to int32[4]. */ - stencil_refs = lp_build_get_stencil_ref(&bld, type, stencil_refs); + stencil_refs[0] = lp_build_get_stencil_ref(&bld, type, stencil_refs_ptr, 0); + + if (stencil[1].enabled) + stencil_refs[1] = + lp_build_get_stencil_ref(&bld, type, stencil_refs_ptr, 1); s_pass_mask = lp_build_stencil_test(&bld, stencil, - stencil_refs, stencil_vals); + stencil_refs, stencil_vals, face); /* apply stencil-fail operator */ { LLVMValueRef s_fail_mask = lp_build_andc(&bld, orig_mask, s_pass_mask); - stencil_vals = lp_build_stencil_op(&bld, stencil, stencil[0].fail_op, + stencil_vals = lp_build_stencil_op(&bld, stencil, S_FAIL_OP, stencil_refs, stencil_vals, - s_fail_mask); + s_fail_mask, face); } } @@ -394,15 +555,15 @@ lp_build_depth_stencil_test(LLVMBuilderRef builder, /* apply Z-fail operator */ z_fail_mask = lp_build_andc(&bld, orig_mask, z_pass); - stencil_vals = lp_build_stencil_op(&bld, stencil, stencil[0].zfail_op, + stencil_vals = lp_build_stencil_op(&bld, stencil, Z_FAIL_OP, stencil_refs, stencil_vals, - z_fail_mask); + z_fail_mask, face); /* apply Z-pass operator */ z_pass_mask = LLVMBuildAnd(bld.builder, orig_mask, z_pass, ""); - stencil_vals = lp_build_stencil_op(&bld, stencil, stencil[0].zpass_op, + stencil_vals = lp_build_stencil_op(&bld, stencil, Z_PASS_OP, stencil_refs, stencil_vals, - z_pass_mask); + z_pass_mask, face); } } else { @@ -410,8 +571,8 @@ lp_build_depth_stencil_test(LLVMBuilderRef builder, * passed the stencil test. */ s_pass_mask = LLVMBuildAnd(bld.builder, orig_mask, s_pass_mask, ""); - stencil_vals = lp_build_stencil_op(&bld, stencil, stencil[0].zpass_op, - stencil_refs, stencil_vals, s_pass_mask); + stencil_vals = lp_build_stencil_op(&bld, stencil, Z_PASS_OP, stencil_refs, + stencil_vals, s_pass_mask, face); } /* Finally, merge/store the z/stencil values */ -- 2.30.2