/************************************************************************** * * Copyright 2010 VMware. * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sub license, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice (including the * next paragraph) shall be included in all copies or substantial portions * of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * **************************************************************************/ #include "util/u_math.h" #include "util/u_memory.h" #include "util/u_simple_list.h" #include "os/os_time.h" #include "gallivm/lp_bld_debug.h" #include "gallivm/lp_bld_init.h" #include "gallivm/lp_bld_intr.h" #include /* for LLVMVerifyFunction */ #include "lp_perf.h" #include "lp_debug.h" #include "lp_flush.h" #include "lp_screen.h" #include "lp_context.h" #include "lp_setup_context.h" #include "lp_rast.h" #include "lp_state.h" #include "lp_state_fs.h" #include "lp_state_setup.h" /* currently organized to interpolate full float[4] attributes even * when some elements are unused. Later, can pack vertex data more * closely. */ struct lp_setup_args { /* Function arguments: */ LLVMValueRef v0; LLVMValueRef v1; LLVMValueRef v2; LLVMValueRef facing; /* boolean */ LLVMValueRef a0; LLVMValueRef dadx; LLVMValueRef dady; /* Derived: */ LLVMValueRef x0_center; LLVMValueRef y0_center; LLVMValueRef dy20_ooa; LLVMValueRef dy01_ooa; LLVMValueRef dx20_ooa; LLVMValueRef dx01_ooa; }; static LLVMTypeRef type4f(void) { return LLVMVectorType(LLVMFloatType(), 4); } /* Equivalent of _mm_setr_ps(a,b,c,d) */ static LLVMValueRef vec4f(LLVMBuilderRef bld, LLVMValueRef a, LLVMValueRef b, LLVMValueRef c, LLVMValueRef d, const char *name) { LLVMValueRef i0 = LLVMConstInt(LLVMInt32Type(), 0, 0); LLVMValueRef i1 = LLVMConstInt(LLVMInt32Type(), 1, 0); LLVMValueRef i2 = LLVMConstInt(LLVMInt32Type(), 2, 0); LLVMValueRef i3 = LLVMConstInt(LLVMInt32Type(), 3, 0); LLVMValueRef res = LLVMGetUndef(type4f()); res = LLVMBuildInsertElement(bld, res, a, i0, ""); res = LLVMBuildInsertElement(bld, res, b, i1, ""); res = LLVMBuildInsertElement(bld, res, c, i2, ""); res = LLVMBuildInsertElement(bld, res, d, i3, name); return res; } /* Equivalent of _mm_set1_ps(a) */ static LLVMValueRef vec4f_from_scalar(LLVMBuilderRef bld, LLVMValueRef a, const char *name) { LLVMValueRef res = LLVMGetUndef(type4f()); int i; for(i = 0; i < 4; ++i) { LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), i, 0); res = LLVMBuildInsertElement(bld, res, a, index, i == 3 ? name : ""); } return res; } static void store_coef(LLVMBuilderRef builder, struct lp_setup_args *args, unsigned slot, LLVMValueRef a0, LLVMValueRef dadx, LLVMValueRef dady) { LLVMValueRef idx = LLVMConstInt(LLVMInt32Type(), slot, 0); LLVMBuildStore(builder, a0, LLVMBuildGEP(builder, args->a0, &idx, 1, "")); LLVMBuildStore(builder, dadx, LLVMBuildGEP(builder, args->dadx, &idx, 1, "")); LLVMBuildStore(builder, dady, LLVMBuildGEP(builder, args->dady, &idx, 1, "")); } static void emit_constant_coef4( LLVMBuilderRef builder, struct lp_setup_args *args, unsigned slot, LLVMValueRef vert, unsigned attr) { LLVMValueRef zero = LLVMConstReal(LLVMFloatType(), 0.0); LLVMValueRef zerovec = vec4f_from_scalar(builder, zero, "zero"); LLVMValueRef idx = LLVMConstInt(LLVMInt32Type(), attr, 0); LLVMValueRef attr_ptr = LLVMBuildGEP(builder, vert, &idx, 1, "attr_ptr"); LLVMValueRef vert_attr = LLVMBuildLoad(builder, attr_ptr, "vert_attr"); store_coef(builder, args, slot, vert_attr, zerovec, zerovec); } /** * Setup the fragment input attribute with the front-facing value. * \param frontface is the triangle front facing? */ static void emit_facing_coef( LLVMBuilderRef builder, struct lp_setup_args *args, unsigned slot ) { LLVMValueRef a0_0 = args->facing; LLVMValueRef a0_0f = LLVMBuildSIToFP(builder, a0_0, LLVMFloatType(), ""); LLVMValueRef zero = LLVMConstReal(LLVMFloatType(), 0.0); LLVMValueRef a0 = vec4f(builder, a0_0f, zero, zero, zero, "facing"); LLVMValueRef zerovec = vec4f_from_scalar(builder, zero, "zero"); store_coef(builder, args, slot, a0, zerovec, zerovec); } static LLVMValueRef vert_attrib(LLVMBuilderRef b, LLVMValueRef vert, int attr, int elem, const char *name) { LLVMValueRef idx[2]; idx[0] = LLVMConstInt(LLVMInt32Type(), attr, 0); idx[1] = LLVMConstInt(LLVMInt32Type(), elem, 0); return LLVMBuildLoad(b, LLVMBuildGEP(b, vert, idx, 2, ""), name); } static void emit_coef4( LLVMBuilderRef b, struct lp_setup_args *args, unsigned slot, LLVMValueRef a0, LLVMValueRef a1, LLVMValueRef a2) { LLVMValueRef dy20_ooa = args->dy20_ooa; LLVMValueRef dy01_ooa = args->dy01_ooa; LLVMValueRef dx20_ooa = args->dx20_ooa; LLVMValueRef dx01_ooa = args->dx01_ooa; LLVMValueRef x0_center = args->x0_center; LLVMValueRef y0_center = args->y0_center; /* XXX: using fsub, fmul on vector types -- does this work?? */ LLVMValueRef da01 = LLVMBuildFSub(b, a0, a1, "da01"); LLVMValueRef da20 = LLVMBuildFSub(b, a2, a0, "da20"); /* Calculate dadx (vec4f) */ LLVMValueRef da01_dy20_ooa = LLVMBuildFMul(b, da01, dy20_ooa, "da01_dy20_ooa"); LLVMValueRef da20_dy01_ooa = LLVMBuildFMul(b, da20, dy01_ooa, "da20_dy01_ooa"); LLVMValueRef dadx = LLVMBuildFSub(b, da01_dy20_ooa, da20_dy01_ooa, "dadx"); /* Calculate dady (vec4f) */ LLVMValueRef da01_dx20_ooa = LLVMBuildFMul(b, da01, dx20_ooa, "da01_dx20_ooa"); LLVMValueRef da20_dx01_ooa = LLVMBuildFMul(b, da20, dx01_ooa, "da20_dx01_ooa"); LLVMValueRef dady = LLVMBuildFSub(b, da20_dx01_ooa, da01_dx20_ooa, "dady"); /* Calculate a0 - the attribute value at the origin */ LLVMValueRef dadx_x0 = LLVMBuildFMul(b, dadx, x0_center, "dadx_x0"); LLVMValueRef dady_y0 = LLVMBuildFMul(b, dady, y0_center, "dady_y0"); LLVMValueRef attr_v0 = LLVMBuildFAdd(b, dadx_x0, dady_y0, "attr_v0"); LLVMValueRef attr_0 = LLVMBuildFSub(b, a0, attr_v0, "attr_0"); store_coef(b, args, slot, attr_0, dadx, dady); } static void emit_linear_coef( LLVMBuilderRef b, struct lp_setup_args *args, unsigned slot, unsigned vert_attr) { LLVMValueRef idx = LLVMConstInt(LLVMInt32Type(), vert_attr, 0); LLVMValueRef a0 = LLVMBuildLoad(b, LLVMBuildGEP(b, args->v0, &idx, 1, ""), "v0a"); LLVMValueRef a1 = LLVMBuildLoad(b, LLVMBuildGEP(b, args->v1, &idx, 1, ""), "v1a"); LLVMValueRef a2 = LLVMBuildLoad(b, LLVMBuildGEP(b, args->v2, &idx, 1, ""), "v2a"); emit_coef4(b, args, slot, a0, a1, a2); } /** * Compute a0, dadx and dady for a perspective-corrected interpolant, * for a triangle. * We basically multiply the vertex value by 1/w before computing * the plane coefficients (a0, dadx, dady). * Later, when we compute the value at a particular fragment position we'll * divide the interpolated value by the interpolated W at that fragment. */ static void emit_perspective_coef( LLVMBuilderRef b, struct lp_setup_args *args, unsigned slot, unsigned vert_attr) { /* premultiply by 1/w (v[0][3] is always 1/w): */ LLVMValueRef idx = LLVMConstInt(LLVMInt32Type(), vert_attr, 0); LLVMValueRef v0a = LLVMBuildLoad(b, LLVMBuildGEP(b, args->v0, &idx, 1, ""), "v0a"); LLVMValueRef v1a = LLVMBuildLoad(b, LLVMBuildGEP(b, args->v1, &idx, 1, ""), "v1a"); LLVMValueRef v2a = LLVMBuildLoad(b, LLVMBuildGEP(b, args->v2, &idx, 1, ""), "v2a"); LLVMValueRef v0_oow = vec4f_from_scalar(b, vert_attrib(b, args->v0, 0, 3, ""), "v0_oow"); LLVMValueRef v1_oow = vec4f_from_scalar(b, vert_attrib(b, args->v1, 0, 3, ""), "v1_oow"); LLVMValueRef v2_oow = vec4f_from_scalar(b, vert_attrib(b, args->v2, 0, 3, ""), "v2_oow"); LLVMValueRef v0_oow_v0a = LLVMBuildFMul(b, v0a, v0_oow, "v0_oow_v0a"); LLVMValueRef v1_oow_v1a = LLVMBuildFMul(b, v1a, v1_oow, "v1_oow_v1a"); LLVMValueRef v2_oow_v2a = LLVMBuildFMul(b, v2a, v2_oow, "v2_oow_v2a"); emit_coef4(b, args, slot, v0_oow_v0a, v1_oow_v1a, v2_oow_v2a); } static void emit_position_coef( LLVMBuilderRef builder, struct lp_setup_args *args, int slot, int attrib ) { emit_linear_coef(builder, args, slot, attrib); } /** * Compute the inputs-> dadx, dady, a0 values. */ static void emit_tri_coef( LLVMBuilderRef builder, const struct lp_setup_variant_key *key, struct lp_setup_args *args ) { unsigned slot; /* The internal position input is in slot zero: */ emit_position_coef(builder, args, 0, 0); /* setup interpolation for all the remaining attributes: */ for (slot = 0; slot < key->num_inputs; slot++) { unsigned vert_attr = key->inputs[slot].src_index; switch (key->inputs[slot].interp) { case LP_INTERP_CONSTANT: if (key->flatshade_first) { emit_constant_coef4(builder, args, slot+1, args->v0, vert_attr); } else { emit_constant_coef4(builder, args, slot+1, args->v2, vert_attr); } break; case LP_INTERP_LINEAR: emit_linear_coef(builder, args, slot+1, vert_attr); break; case LP_INTERP_PERSPECTIVE: emit_perspective_coef(builder, args, slot+1, vert_attr); break; case LP_INTERP_POSITION: /* * The generated pixel interpolators will pick up the coeffs from * slot 0. */ break; case LP_INTERP_FACING: emit_facing_coef(builder, args, slot+1); break; default: assert(0); } } } /* XXX: This is generic code, share with fs/vs codegen: */ static lp_jit_setup_triangle finalize_function(struct llvmpipe_screen *screen, LLVMBuilderRef builder, LLVMValueRef function) { void *f; /* Verify the LLVM IR. If invalid, dump and abort */ #ifdef DEBUG if (LLVMVerifyFunction(function, LLVMPrintMessageAction)) { if (1) lp_debug_dump_value(function); abort(); } #endif /* Apply optimizations to LLVM IR */ LLVMRunFunctionPassManager(screen->pass, function); if (gallivm_debug & GALLIVM_DEBUG_IR) { /* Print the LLVM IR to stderr */ lp_debug_dump_value(function); debug_printf("\n"); } /* * Translate the LLVM IR into machine code. */ f = LLVMGetPointerToGlobal(screen->engine, function); if (gallivm_debug & GALLIVM_DEBUG_ASM) { lp_disassemble(f); } lp_func_delete_body(function); return f; } /* XXX: Generic code: */ static void lp_emit_emms(LLVMBuilderRef builder) { #ifdef PIPE_ARCH_X86 /* Avoid corrupting the FPU stack on 32bit OSes. */ lp_build_intrinsic(builder, "llvm.x86.mmx.emms", LLVMVoidType(), NULL, 0); #endif } /* XXX: generic code: */ static void set_noalias(LLVMBuilderRef builder, LLVMValueRef function, const LLVMTypeRef *arg_types, int nr_args) { int i; for(i = 0; i < Elements(arg_types); ++i) if(LLVMGetTypeKind(arg_types[i]) == LLVMPointerTypeKind) LLVMAddAttribute(LLVMGetParam(function, i), LLVMNoAliasAttribute); } static void init_args(LLVMBuilderRef b, struct lp_setup_args *args, const struct lp_setup_variant *variant) { LLVMValueRef v0_x = vert_attrib(b, args->v0, 0, 0, "v0_x"); LLVMValueRef v0_y = vert_attrib(b, args->v0, 0, 1, "v0_y"); LLVMValueRef v1_x = vert_attrib(b, args->v1, 0, 0, "v1_x"); LLVMValueRef v1_y = vert_attrib(b, args->v1, 0, 1, "v1_y"); LLVMValueRef v2_x = vert_attrib(b, args->v2, 0, 0, "v2_x"); LLVMValueRef v2_y = vert_attrib(b, args->v2, 0, 1, "v2_y"); LLVMValueRef pixel_center = LLVMConstReal(LLVMFloatType(), variant->key.pixel_center_half ? 0.5 : 0); LLVMValueRef x0_center = LLVMBuildFSub(b, v0_x, pixel_center, "x0_center" ); LLVMValueRef y0_center = LLVMBuildFSub(b, v0_y, pixel_center, "y0_center" ); LLVMValueRef dx01 = LLVMBuildFSub(b, v0_x, v1_x, "dx01"); LLVMValueRef dy01 = LLVMBuildFSub(b, v0_y, v1_y, "dy01"); LLVMValueRef dx20 = LLVMBuildFSub(b, v2_x, v0_x, "dx20"); LLVMValueRef dy20 = LLVMBuildFSub(b, v2_y, v0_y, "dy20"); LLVMValueRef one = LLVMConstReal(LLVMFloatType(), 1.0); LLVMValueRef e = LLVMBuildFMul(b, dx01, dy20, "e"); LLVMValueRef f = LLVMBuildFMul(b, dx20, dy01, "f"); LLVMValueRef ooa = LLVMBuildFDiv(b, one, LLVMBuildFSub(b, e, f, ""), "ooa"); LLVMValueRef dy20_ooa = LLVMBuildFMul(b, dy20, ooa, "dy20_ooa"); LLVMValueRef dy01_ooa = LLVMBuildFMul(b, dy01, ooa, "dy01_ooa"); LLVMValueRef dx20_ooa = LLVMBuildFMul(b, dx20, ooa, "dx20_ooa"); LLVMValueRef dx01_ooa = LLVMBuildFMul(b, dx01, ooa, "dx01_ooa"); args->dy20_ooa = vec4f_from_scalar(b, dy20_ooa, "dy20_ooa_4f"); args->dy01_ooa = vec4f_from_scalar(b, dy01_ooa, "dy01_ooa_4f"); args->dx20_ooa = vec4f_from_scalar(b, dx20_ooa, "dx20_ooa_4f"); args->dx01_ooa = vec4f_from_scalar(b, dx01_ooa, "dx01_ooa_4f"); args->x0_center = vec4f_from_scalar(b, x0_center, "x0_center_4f"); args->y0_center = vec4f_from_scalar(b, y0_center, "y0_center_4f"); } /** * Generate the runtime callable function for the coefficient calculation. * */ static struct lp_setup_variant * generate_setup_variant(struct llvmpipe_screen *screen, struct lp_setup_variant_key *key) { struct lp_setup_variant *variant = NULL; struct lp_setup_args args; char func_name[256]; LLVMTypeRef vec4f_type; LLVMTypeRef func_type; LLVMTypeRef arg_types[7]; LLVMBasicBlockRef block; LLVMBuilderRef builder; int64_t t0, t1; if (0) goto fail; variant = CALLOC_STRUCT(lp_setup_variant); if (variant == NULL) goto fail; if (LP_DEBUG & DEBUG_COUNTERS) { t0 = os_time_get(); } memcpy(&variant->key, key, key->size); variant->list_item_global.base = variant; util_snprintf(func_name, sizeof(func_name), "fs%u_setup%u", 0, variant->no); /* Currently always deal with full 4-wide vertex attributes from * the vertices. */ vec4f_type = LLVMVectorType(LLVMFloatType(), 4); arg_types[0] = LLVMPointerType(vec4f_type, 0); /* v0 */ arg_types[1] = LLVMPointerType(vec4f_type, 0); /* v1 */ arg_types[2] = LLVMPointerType(vec4f_type, 0); /* v2 */ arg_types[3] = LLVMInt32Type(); /* facing */ arg_types[4] = LLVMPointerType(vec4f_type, 0); /* a0, aligned */ arg_types[5] = LLVMPointerType(vec4f_type, 0); /* dadx, aligned */ arg_types[6] = LLVMPointerType(vec4f_type, 0); /* dady, aligned */ func_type = LLVMFunctionType(LLVMVoidType(), arg_types, Elements(arg_types), 0); variant->function = LLVMAddFunction(screen->module, func_name, func_type); if (!variant->function) goto fail; LLVMSetFunctionCallConv(variant->function, LLVMCCallConv); args.v0 = LLVMGetParam(variant->function, 0); args.v1 = LLVMGetParam(variant->function, 1); args.v2 = LLVMGetParam(variant->function, 2); args.facing = LLVMGetParam(variant->function, 3); args.a0 = LLVMGetParam(variant->function, 4); args.dadx = LLVMGetParam(variant->function, 5); args.dady = LLVMGetParam(variant->function, 6); lp_build_name(args.v0, "in_v0"); lp_build_name(args.v1, "in_v1"); lp_build_name(args.v2, "in_v2"); lp_build_name(args.facing, "in_facing"); lp_build_name(args.a0, "out_a0"); lp_build_name(args.dadx, "out_dadx"); lp_build_name(args.dady, "out_dady"); /* * Function body */ block = LLVMAppendBasicBlock(variant->function, "entry"); builder = LLVMCreateBuilder(); LLVMPositionBuilderAtEnd(builder, block); set_noalias(builder, variant->function, arg_types, Elements(arg_types)); init_args(builder, &args, variant); emit_tri_coef(builder, &variant->key, &args); lp_emit_emms(builder); LLVMBuildRetVoid(builder); LLVMDisposeBuilder(builder); variant->jit_function = finalize_function(screen, builder, variant->function); if (!variant->jit_function) goto fail; /* * Update timing information: */ if (LP_DEBUG & DEBUG_COUNTERS) { t1 = os_time_get(); LP_COUNT_ADD(llvm_compile_time, t1 - t0); LP_COUNT_ADD(nr_llvm_compiles, 1); } return variant; fail: if (variant) { if (variant->function) { if (variant->jit_function) LLVMFreeMachineCodeForFunction(screen->engine, variant->function); LLVMDeleteFunction(variant->function); } FREE(variant); } return NULL; } static void lp_make_setup_variant_key(struct llvmpipe_context *lp, struct lp_setup_variant_key *key) { struct lp_fragment_shader *fs = lp->fs; unsigned i; assert(sizeof key->inputs[0] == sizeof(ushort)); key->num_inputs = fs->info.base.num_inputs; key->flatshade_first = lp->rasterizer->flatshade_first; key->pixel_center_half = lp->rasterizer->gl_rasterization_rules; key->size = Offset(struct lp_setup_variant_key, inputs[key->num_inputs]); key->pad = 0; memcpy(key->inputs, fs->inputs, key->num_inputs * sizeof key->inputs[0]); for (i = 0; i < key->num_inputs; i++) { if (key->inputs[i].interp == LP_INTERP_COLOR) { if (lp->rasterizer->flatshade) key->inputs[i].interp = LP_INTERP_CONSTANT; else key->inputs[i].interp = LP_INTERP_LINEAR; } } } static void remove_setup_variant(struct llvmpipe_context *lp, struct lp_setup_variant *variant) { struct llvmpipe_screen *screen = llvmpipe_screen(lp->pipe.screen); if (gallivm_debug & GALLIVM_DEBUG_IR) { debug_printf("llvmpipe: del setup_variant #%u total %u\n", variant->no, lp->nr_setup_variants); } if (variant->function) { if (variant->jit_function) LLVMFreeMachineCodeForFunction(screen->engine, variant->function); LLVMDeleteFunction(variant->function); } remove_from_list(&variant->list_item_global); lp->nr_setup_variants--; FREE(variant); } /* When the number of setup variants exceeds a threshold, cull a * fraction (currently a quarter) of them. */ static void cull_setup_variants(struct llvmpipe_context *lp) { struct pipe_context *pipe = &lp->pipe; int i; /* * XXX: we need to flush the context until we have some sort of reference * counting in fragment shaders as they may still be binned * Flushing alone might not be sufficient we need to wait on it too. */ llvmpipe_finish(pipe, __FUNCTION__); for (i = 0; i < LP_MAX_SETUP_VARIANTS / 4; i++) { struct lp_setup_variant_list_item *item = last_elem(&lp->setup_variants_list); remove_setup_variant(lp, item->base); } } /** * Update fragment/vertex shader linkage state. This is called just * prior to drawing something when some fragment-related state has * changed. */ void llvmpipe_update_setup(struct llvmpipe_context *lp) { struct llvmpipe_screen *screen = llvmpipe_screen(lp->pipe.screen); struct lp_setup_variant_key *key = &lp->setup_variant.key; struct lp_setup_variant *variant = NULL; struct lp_setup_variant_list_item *li; lp_make_setup_variant_key(lp, key); foreach(li, &lp->setup_variants_list) { if(li->base->key.size == key->size && memcmp(&li->base->key, key, key->size) == 0) { variant = li->base; break; } } if (variant) { move_to_head(&lp->setup_variants_list, &variant->list_item_global); } else { if (lp->nr_setup_variants >= LP_MAX_SETUP_VARIANTS) { cull_setup_variants(lp); } variant = generate_setup_variant(screen, key); insert_at_head(&lp->setup_variants_list, &variant->list_item_global); lp->nr_setup_variants++; } lp_setup_set_setup_variant(lp->setup, variant); } void lp_delete_setup_variants(struct llvmpipe_context *lp) { struct lp_setup_variant_list_item *li; li = first_elem(&lp->setup_variants_list); while(!at_end(&lp->setup_variants_list, li)) { struct lp_setup_variant_list_item *next = next_elem(li); remove_setup_variant(lp, li->base); li = next; } } void lp_dump_setup_coef( const struct lp_setup_variant_key *key, const float (*sa0)[4], const float (*sdadx)[4], const float (*sdady)[4]) { int i, slot; for (i = 0; i < NUM_CHANNELS; i++) { float a0 = sa0 [0][i]; float dadx = sdadx[0][i]; float dady = sdady[0][i]; debug_printf("POS.%c: a0 = %f, dadx = %f, dady = %f\n", "xyzw"[i], a0, dadx, dady); } for (slot = 0; slot < key->num_inputs; slot++) { unsigned usage_mask = key->inputs[slot].usage_mask; for (i = 0; i < NUM_CHANNELS; i++) { if (usage_mask & (1 << i)) { float a0 = sa0 [1 + slot][i]; float dadx = sdadx[1 + slot][i]; float dady = sdady[1 + slot][i]; debug_printf("IN[%u].%c: a0 = %f, dadx = %f, dady = %f\n", slot, "xyzw"[i], a0, dadx, dady); } } } }