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Diffstat (limited to 'libpixelflinger/codeflinger/blending.cpp')
| -rw-r--r-- | libpixelflinger/codeflinger/blending.cpp | 682 |
1 files changed, 682 insertions, 0 deletions
diff --git a/libpixelflinger/codeflinger/blending.cpp b/libpixelflinger/codeflinger/blending.cpp new file mode 100644 index 0000000..f10217b --- /dev/null +++ b/libpixelflinger/codeflinger/blending.cpp @@ -0,0 +1,682 @@ +/* libs/pixelflinger/codeflinger/blending.cpp +** +** Copyright 2006, The Android Open Source Project +** +** Licensed under the Apache License, Version 2.0 (the "License"); +** you may not use this file except in compliance with the License. +** You may obtain a copy of the License at +** +** http://www.apache.org/licenses/LICENSE-2.0 +** +** Unless required by applicable law or agreed to in writing, software +** distributed under the License is distributed on an "AS IS" BASIS, +** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +** See the License for the specific language governing permissions and +** limitations under the License. +*/ + +#include <assert.h> +#include <stdint.h> +#include <stdlib.h> +#include <stdio.h> +#include <sys/types.h> + +#include <cutils/log.h> + +#include "codeflinger/GGLAssembler.h" + + +namespace android { + +void GGLAssembler::build_fog( + component_t& temp, // incomming fragment / output + int component, + Scratch& regs) +{ + if (mInfo[component].fog) { + Scratch scratches(registerFile()); + comment("fog"); + + integer_t fragment(temp.reg, temp.h, temp.flags); + if (!(temp.flags & CORRUPTIBLE)) { + temp.reg = regs.obtain(); + temp.flags |= CORRUPTIBLE; + } + + integer_t fogColor(scratches.obtain(), 8, CORRUPTIBLE); + LDRB(AL, fogColor.reg, mBuilderContext.Rctx, + immed12_pre(GGL_OFFSETOF(state.fog.color[component]))); + + integer_t factor(scratches.obtain(), 16, CORRUPTIBLE); + CONTEXT_LOAD(factor.reg, generated_vars.f); + + // clamp fog factor (TODO: see if there is a way to guarantee + // we won't overflow, when setting the iterators) + BIC(AL, 0, factor.reg, factor.reg, reg_imm(factor.reg, ASR, 31)); + CMP(AL, factor.reg, imm( 0x10000 )); + MOV(HS, 0, factor.reg, imm( 0x10000 )); + + build_blendFOneMinusF(temp, factor, fragment, fogColor); + } +} + +void GGLAssembler::build_blending( + component_t& temp, // incomming fragment / output + const pixel_t& pixel, // framebuffer + int component, + Scratch& regs) +{ + if (!mInfo[component].blend) + return; + + int fs = component==GGLFormat::ALPHA ? mBlendSrcA : mBlendSrc; + int fd = component==GGLFormat::ALPHA ? mBlendDstA : mBlendDst; + if (fs==GGL_SRC_ALPHA_SATURATE && component==GGLFormat::ALPHA) + fs = GGL_ONE; + const int blending = blending_codes(fs, fd); + if (!temp.size()) { + // here, blending will produce something which doesn't depend on + // that component (eg: GL_ZERO:GL_*), so the register has not been + // allocated yet. Will never be used as a source. + temp = component_t(regs.obtain(), CORRUPTIBLE); + } + + // we are doing real blending... + // fb: extracted dst + // fragment: extracted src + // temp: component_t(fragment) and result + + // scoped register allocator + Scratch scratches(registerFile()); + comment("blending"); + + // we can optimize these cases a bit... + // (1) saturation is not needed + // (2) we can use only one multiply instead of 2 + // (3) we can reduce the register pressure + // R = S*f + D*(1-f) = (S-D)*f + D + // R = S*(1-f) + D*f = (D-S)*f + S + + const bool same_factor_opt1 = + (fs==GGL_DST_COLOR && fd==GGL_ONE_MINUS_DST_COLOR) || + (fs==GGL_SRC_COLOR && fd==GGL_ONE_MINUS_SRC_COLOR) || + (fs==GGL_DST_ALPHA && fd==GGL_ONE_MINUS_DST_ALPHA) || + (fs==GGL_SRC_ALPHA && fd==GGL_ONE_MINUS_SRC_ALPHA); + + const bool same_factor_opt2 = + (fs==GGL_ONE_MINUS_DST_COLOR && fd==GGL_DST_COLOR) || + (fs==GGL_ONE_MINUS_SRC_COLOR && fd==GGL_SRC_COLOR) || + (fs==GGL_ONE_MINUS_DST_ALPHA && fd==GGL_DST_ALPHA) || + (fs==GGL_ONE_MINUS_SRC_ALPHA && fd==GGL_SRC_ALPHA); + + + // XXX: we could also optimize these cases: + // R = S*f + D*f = (S+D)*f + // R = S*(1-f) + D*(1-f) = (S+D)*(1-f) + // R = S*D + D*S = 2*S*D + + + // see if we need to extract 'component' from the destination (fb) + integer_t fb; + if (blending & (BLEND_DST|FACTOR_DST)) { + fb.setTo(scratches.obtain(), 32); + extract(fb, pixel, component); + if (mDithering) { + // XXX: maybe what we should do instead, is simply + // expand fb -or- fragment to the larger of the two + if (fb.size() < temp.size()) { + // for now we expand 'fb' to min(fragment, 8) + int new_size = temp.size() < 8 ? temp.size() : 8; + expand(fb, fb, new_size); + } + } + } + + + // convert input fragment to integer_t + if (temp.l && (temp.flags & CORRUPTIBLE)) { + MOV(AL, 0, temp.reg, reg_imm(temp.reg, LSR, temp.l)); + temp.h -= temp.l; + temp.l = 0; + } + integer_t fragment(temp.reg, temp.size(), temp.flags); + + // if not done yet, convert input fragment to integer_t + if (temp.l) { + // here we know temp is not CORRUPTIBLE + fragment.reg = scratches.obtain(); + MOV(AL, 0, fragment.reg, reg_imm(temp.reg, LSR, temp.l)); + fragment.flags |= CORRUPTIBLE; + } + + if (!(temp.flags & CORRUPTIBLE)) { + // temp is not corruptible, but since it's the destination it + // will be modified, so we need to allocate a new register. + temp.reg = regs.obtain(); + temp.flags &= ~CORRUPTIBLE; + fragment.flags &= ~CORRUPTIBLE; + } + + if ((blending & BLEND_SRC) && !same_factor_opt1) { + // source (fragment) is needed for the blending stage + // so it's not CORRUPTIBLE (unless we're doing same_factor_opt1) + fragment.flags &= ~CORRUPTIBLE; + } + + + if (same_factor_opt1) { + // R = S*f + D*(1-f) = (S-D)*f + D + integer_t factor; + build_blend_factor(factor, fs, + component, pixel, fragment, fb, scratches); + // fb is always corruptible from this point + fb.flags |= CORRUPTIBLE; + build_blendFOneMinusF(temp, factor, fragment, fb); + } else if (same_factor_opt2) { + // R = S*(1-f) + D*f = (D-S)*f + S + integer_t factor; + // fb is always corrruptible here + fb.flags |= CORRUPTIBLE; + build_blend_factor(factor, fd, + component, pixel, fragment, fb, scratches); + build_blendOneMinusFF(temp, factor, fragment, fb); + } else { + integer_t src_factor; + integer_t dst_factor; + + // if destination (fb) is not needed for the blending stage, + // then it can be marked as CORRUPTIBLE + if (!(blending & BLEND_DST)) { + fb.flags |= CORRUPTIBLE; + } + + // XXX: try to mark some registers as CORRUPTIBLE + // in most case we could make those corruptible + // when we're processing the last component + // but not always, for instance + // when fragment is constant and not reloaded + // when fb is needed for logic-ops or masking + // when a register is aliased (for instance with mAlphaSource) + + // blend away... + if (fs==GGL_ZERO) { + if (fd==GGL_ZERO) { // R = 0 + // already taken care of + } else if (fd==GGL_ONE) { // R = D + // already taken care of + } else { // R = D*fd + // compute fd + build_blend_factor(dst_factor, fd, + component, pixel, fragment, fb, scratches); + mul_factor(temp, fb, dst_factor); + } + } else if (fs==GGL_ONE) { + if (fd==GGL_ZERO) { // R = S + // NOP, taken care of + } else if (fd==GGL_ONE) { // R = S + D + component_add(temp, fb, fragment); // args order matters + component_sat(temp); + } else { // R = S + D*fd + // compute fd + build_blend_factor(dst_factor, fd, + component, pixel, fragment, fb, scratches); + mul_factor_add(temp, fb, dst_factor, component_t(fragment)); + if (fd==GGL_ONE_MINUS_SRC_ALPHA) { + // XXX: in theory this is not correct, we should + // saturate here. However, this mode is often + // used for displaying alpha-premultiplied graphics, + // in which case, saturation is not necessary. + // unfortunatelly, we have no way to know. + // This is a case, where we sacrifice correctness for + // performance. we should probably have some heuristics. + } else { + component_sat(temp); + } + } + } else { + // compute fs + build_blend_factor(src_factor, fs, + component, pixel, fragment, fb, scratches); + if (fd==GGL_ZERO) { // R = S*fs + mul_factor(temp, fragment, src_factor); + } else if (fd==GGL_ONE) { // R = S*fs + D + mul_factor_add(temp, fragment, src_factor, component_t(fb)); + component_sat(temp); + } else { // R = S*fs + D*fd + mul_factor(temp, fragment, src_factor); + if (scratches.isUsed(src_factor.reg)) + scratches.recycle(src_factor.reg); + // compute fd + build_blend_factor(dst_factor, fd, + component, pixel, fragment, fb, scratches); + mul_factor_add(temp, fb, dst_factor, temp); + if (!same_factor_opt1 && !same_factor_opt2) { + component_sat(temp); + } + } + } + } + + // now we can be corrupted (it's the dest) + temp.flags |= CORRUPTIBLE; +} + +void GGLAssembler::build_blend_factor( + integer_t& factor, int f, int component, + const pixel_t& dst_pixel, + integer_t& fragment, + integer_t& fb, + Scratch& scratches) +{ + integer_t src_alpha(fragment); + + // src_factor/dst_factor won't be used after blending, + // so it's fine to mark them as CORRUPTIBLE (if not aliased) + factor.flags |= CORRUPTIBLE; + + switch(f) { + case GGL_ONE_MINUS_SRC_ALPHA: + case GGL_SRC_ALPHA: + if (component==GGLFormat::ALPHA && !isAlphaSourceNeeded()) { + // we're processing alpha, so we already have + // src-alpha in fragment, and we need src-alpha just this time. + } else { + // alpha-src will be needed for other components + if (!mBlendFactorCached || mBlendFactorCached==f) { + src_alpha = mAlphaSource; + factor = mAlphaSource; + factor.flags &= ~CORRUPTIBLE; + // we already computed the blend factor before, nothing to do. + if (mBlendFactorCached) + return; + // this is the first time, make sure to compute the blend + // factor properly. + mBlendFactorCached = f; + break; + } else { + // we have a cached alpha blend factor, but we want another one, + // this should really not happen because by construction, + // we cannot have BOTH source and destination + // blend factors use ALPHA *and* ONE_MINUS_ALPHA (because + // the blending stage uses the f/(1-f) optimization + + // for completeness, we handle this case though. Since there + // are only 2 choices, this meens we want "the other one" + // (1-factor) + factor = mAlphaSource; + factor.flags &= ~CORRUPTIBLE; + RSB(AL, 0, factor.reg, factor.reg, imm((1<<factor.s))); + mBlendFactorCached = f; + return; + } + } + // fall-through... + case GGL_ONE_MINUS_DST_COLOR: + case GGL_DST_COLOR: + case GGL_ONE_MINUS_SRC_COLOR: + case GGL_SRC_COLOR: + case GGL_ONE_MINUS_DST_ALPHA: + case GGL_DST_ALPHA: + case GGL_SRC_ALPHA_SATURATE: + // help us find out what register we can use for the blend-factor + // CORRUPTIBLE registers are chosen first, or a new one is allocated. + if (fragment.flags & CORRUPTIBLE) { + factor.setTo(fragment.reg, 32, CORRUPTIBLE); + fragment.flags &= ~CORRUPTIBLE; + } else if (fb.flags & CORRUPTIBLE) { + factor.setTo(fb.reg, 32, CORRUPTIBLE); + fb.flags &= ~CORRUPTIBLE; + } else { + factor.setTo(scratches.obtain(), 32, CORRUPTIBLE); + } + break; + } + + // XXX: doesn't work if size==1 + + switch(f) { + case GGL_ONE_MINUS_DST_COLOR: + case GGL_DST_COLOR: + factor.s = fb.s; + ADD(AL, 0, factor.reg, fb.reg, reg_imm(fb.reg, LSR, fb.s-1)); + break; + case GGL_ONE_MINUS_SRC_COLOR: + case GGL_SRC_COLOR: + factor.s = fragment.s; + ADD(AL, 0, factor.reg, fragment.reg, + reg_imm(fragment.reg, LSR, fragment.s-1)); + break; + case GGL_ONE_MINUS_SRC_ALPHA: + case GGL_SRC_ALPHA: + factor.s = src_alpha.s; + ADD(AL, 0, factor.reg, src_alpha.reg, + reg_imm(src_alpha.reg, LSR, src_alpha.s-1)); + break; + case GGL_ONE_MINUS_DST_ALPHA: + case GGL_DST_ALPHA: + // XXX: should be precomputed + extract(factor, dst_pixel, GGLFormat::ALPHA); + ADD(AL, 0, factor.reg, factor.reg, + reg_imm(factor.reg, LSR, factor.s-1)); + break; + case GGL_SRC_ALPHA_SATURATE: + // XXX: should be precomputed + // XXX: f = min(As, 1-Ad) + // btw, we're guaranteed that Ad's size is <= 8, because + // it's extracted from the framebuffer + break; + } + + switch(f) { + case GGL_ONE_MINUS_DST_COLOR: + case GGL_ONE_MINUS_SRC_COLOR: + case GGL_ONE_MINUS_DST_ALPHA: + case GGL_ONE_MINUS_SRC_ALPHA: + RSB(AL, 0, factor.reg, factor.reg, imm((1<<factor.s))); + } + + // don't need more than 8-bits for the blend factor + // and this will prevent overflows in the multiplies later + if (factor.s > 8) { + MOV(AL, 0, factor.reg, reg_imm(factor.reg, LSR, factor.s-8)); + factor.s = 8; + } +} + +int GGLAssembler::blending_codes(int fs, int fd) +{ + int blending = 0; + switch(fs) { + case GGL_ONE: + blending |= BLEND_SRC; + break; + + case GGL_ONE_MINUS_DST_COLOR: + case GGL_DST_COLOR: + blending |= FACTOR_DST|BLEND_SRC; + break; + case GGL_ONE_MINUS_DST_ALPHA: + case GGL_DST_ALPHA: + // no need to extract 'component' from the destination + // for the blend factor, because we need ALPHA only. + blending |= BLEND_SRC; + break; + + case GGL_ONE_MINUS_SRC_COLOR: + case GGL_SRC_COLOR: + blending |= FACTOR_SRC|BLEND_SRC; + break; + case GGL_ONE_MINUS_SRC_ALPHA: + case GGL_SRC_ALPHA: + case GGL_SRC_ALPHA_SATURATE: + blending |= FACTOR_SRC|BLEND_SRC; + break; + } + switch(fd) { + case GGL_ONE: + blending |= BLEND_DST; + break; + + case GGL_ONE_MINUS_DST_COLOR: + case GGL_DST_COLOR: + blending |= FACTOR_DST|BLEND_DST; + break; + case GGL_ONE_MINUS_DST_ALPHA: + case GGL_DST_ALPHA: + blending |= FACTOR_DST|BLEND_DST; + break; + + case GGL_ONE_MINUS_SRC_COLOR: + case GGL_SRC_COLOR: + blending |= FACTOR_SRC|BLEND_DST; + break; + case GGL_ONE_MINUS_SRC_ALPHA: + case GGL_SRC_ALPHA: + // no need to extract 'component' from the source + // for the blend factor, because we need ALPHA only. + blending |= BLEND_DST; + break; + } + return blending; +} + +// --------------------------------------------------------------------------- + +void GGLAssembler::build_blendFOneMinusF( + component_t& temp, + const integer_t& factor, + const integer_t& fragment, + const integer_t& fb) +{ + // R = S*f + D*(1-f) = (S-D)*f + D + Scratch scratches(registerFile()); + // compute S-D + integer_t diff(fragment.flags & CORRUPTIBLE ? + fragment.reg : scratches.obtain(), fb.size(), CORRUPTIBLE); + const int shift = fragment.size() - fb.size(); + if (shift>0) RSB(AL, 0, diff.reg, fb.reg, reg_imm(fragment.reg, LSR, shift)); + else if (shift<0) RSB(AL, 0, diff.reg, fb.reg, reg_imm(fragment.reg, LSL,-shift)); + else RSB(AL, 0, diff.reg, fb.reg, fragment.reg); + mul_factor_add(temp, diff, factor, component_t(fb)); +} + +void GGLAssembler::build_blendOneMinusFF( + component_t& temp, + const integer_t& factor, + const integer_t& fragment, + const integer_t& fb) +{ + // R = S*f + D*(1-f) = (S-D)*f + D + Scratch scratches(registerFile()); + // compute D-S + integer_t diff(fb.flags & CORRUPTIBLE ? + fb.reg : scratches.obtain(), fb.size(), CORRUPTIBLE); + const int shift = fragment.size() - fb.size(); + if (shift>0) SUB(AL, 0, diff.reg, fb.reg, reg_imm(fragment.reg, LSR, shift)); + else if (shift<0) SUB(AL, 0, diff.reg, fb.reg, reg_imm(fragment.reg, LSL,-shift)); + else SUB(AL, 0, diff.reg, fb.reg, fragment.reg); + mul_factor_add(temp, diff, factor, component_t(fragment)); +} + +// --------------------------------------------------------------------------- + +void GGLAssembler::mul_factor( component_t& d, + const integer_t& v, + const integer_t& f) +{ + int vs = v.size(); + int fs = f.size(); + int ms = vs+fs; + + // XXX: we could have special cases for 1 bit mul + + // all this code below to use the best multiply instruction + // wrt the parameters size. We take advantage of the fact + // that the 16-bits multiplies allow a 16-bit shift + // The trick is that we just make sure that we have at least 8-bits + // per component (which is enough for a 8 bits display). + + int xy; + int vshift = 0; + int fshift = 0; + int smulw = 0; + + if (vs<16) { + if (fs<16) { + xy = xyBB; + } else if (GGL_BETWEEN(fs, 24, 31)) { + ms -= 16; + xy = xyTB; + } else { + // eg: 15 * 18 -> 15 * 15 + fshift = fs - 15; + ms -= fshift; + xy = xyBB; + } + } else if (GGL_BETWEEN(vs, 24, 31)) { + if (fs<16) { + ms -= 16; + xy = xyTB; + } else if (GGL_BETWEEN(fs, 24, 31)) { + ms -= 32; + xy = xyTT; + } else { + // eg: 24 * 18 -> 8 * 18 + fshift = fs - 15; + ms -= 16 + fshift; + xy = xyTB; + } + } else { + if (fs<16) { + // eg: 18 * 15 -> 15 * 15 + vshift = vs - 15; + ms -= vshift; + xy = xyBB; + } else if (GGL_BETWEEN(fs, 24, 31)) { + // eg: 18 * 24 -> 15 * 8 + vshift = vs - 15; + ms -= 16 + vshift; + xy = xyBT; + } else { + // eg: 18 * 18 -> (15 * 18)>>16 + fshift = fs - 15; + ms -= 16 + fshift; + xy = yB; //XXX SMULWB + smulw = 1; + } + } + + LOGE_IF(ms>=32, "mul_factor overflow vs=%d, fs=%d", vs, fs); + + int vreg = v.reg; + int freg = f.reg; + if (vshift) { + MOV(AL, 0, d.reg, reg_imm(vreg, LSR, vshift)); + vreg = d.reg; + } + if (fshift) { + MOV(AL, 0, d.reg, reg_imm(vreg, LSR, fshift)); + freg = d.reg; + } + if (smulw) SMULW(AL, xy, d.reg, vreg, freg); + else SMUL(AL, xy, d.reg, vreg, freg); + + + d.h = ms; + if (mDithering) { + d.l = 0; + } else { + d.l = fs; + d.flags |= CLEAR_LO; + } +} + +void GGLAssembler::mul_factor_add( component_t& d, + const integer_t& v, + const integer_t& f, + const component_t& a) +{ + // XXX: we could have special cases for 1 bit mul + Scratch scratches(registerFile()); + + int vs = v.size(); + int fs = f.size(); + int as = a.h; + int ms = vs+fs; + + LOGE_IF(ms>=32, "mul_factor_add overflow vs=%d, fs=%d, as=%d", vs, fs, as); + + integer_t add(a.reg, a.h, a.flags); + + // 'a' is a component_t but it is guaranteed to have + // its high bits set to 0. However in the dithering case, + // we can't get away with truncating the potentially bad bits + // so extraction is needed. + + if ((mDithering) && (a.size() < ms)) { + // we need to expand a + if (!(a.flags & CORRUPTIBLE)) { + // ... but it's not corruptible, so we need to pick a + // temporary register. + // Try to uses the destination register first (it's likely + // to be usable, unless it aliases an input). + if (d.reg!=a.reg && d.reg!=v.reg && d.reg!=f.reg) { + add.reg = d.reg; + } else { + add.reg = scratches.obtain(); + } + } + expand(add, a, ms); // extracts and expands + as = ms; + } + + if (ms == as) { + if (vs<16 && fs<16) SMLABB(AL, d.reg, v.reg, f.reg, add.reg); + else MLA(AL, 0, d.reg, v.reg, f.reg, add.reg); + } else { + int temp = d.reg; + if (temp == add.reg) { + // the mul will modify add.reg, we need an intermediary reg + if (v.flags & CORRUPTIBLE) temp = v.reg; + else if (f.flags & CORRUPTIBLE) temp = f.reg; + else temp = scratches.obtain(); + } + + if (vs<16 && fs<16) SMULBB(AL, temp, v.reg, f.reg); + else MUL(AL, 0, temp, v.reg, f.reg); + + if (ms>as) { + ADD(AL, 0, d.reg, temp, reg_imm(add.reg, LSL, ms-as)); + } else if (ms<as) { + // not sure if we should expand the mul instead? + ADD(AL, 0, d.reg, temp, reg_imm(add.reg, LSR, as-ms)); + } + } + + d.h = ms; + if (mDithering) { + d.l = a.l; + } else { + d.l = fs>a.l ? fs : a.l; + d.flags |= CLEAR_LO; + } +} + +void GGLAssembler::component_add(component_t& d, + const integer_t& dst, const integer_t& src) +{ + // here we're guaranteed that fragment.size() >= fb.size() + const int shift = src.size() - dst.size(); + if (!shift) { + ADD(AL, 0, d.reg, src.reg, dst.reg); + } else { + ADD(AL, 0, d.reg, src.reg, reg_imm(dst.reg, LSL, shift)); + } + + d.h = src.size(); + if (mDithering) { + d.l = 0; + } else { + d.l = shift; + d.flags |= CLEAR_LO; + } +} + +void GGLAssembler::component_sat(const component_t& v) +{ + const int one = ((1<<v.size())-1)<<v.l; + CMP(AL, v.reg, imm( 1<<v.h )); + if (isValidImmediate(one)) { + MOV(HS, 0, v.reg, imm( one )); + } else if (isValidImmediate(~one)) { + MVN(HS, 0, v.reg, imm( ~one )); + } else { + MOV(HS, 0, v.reg, imm( 1<<v.h )); + SUB(HS, 0, v.reg, v.reg, imm( 1<<v.l )); + } +} + +// ---------------------------------------------------------------------------- + +}; // namespace android + |