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(svn r26247) -Fix [FS#5854, FS#5855]: Possible out of bounds reads with the sse blitters (MJP)

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This commit is contained in:
rubidium
2014-01-13 17:54:24 +00:00
parent 54a898be33
commit a942619911
6 changed files with 164 additions and 208 deletions
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80
src/blitter/32bpp_sse2.cpp
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@@ -70,18 +70,18 @@ inline void Blitter_32bppSSE2::Draw(const Blitter::BlitterParams *bp, ZoomLevel
case RM_WITH_SKIP: {
for (uint x = (uint) effective_width / 2; x > 0; x--) {
__m128i srcABCD = _mm_loadu_si128((const __m128i*) src);
__m128i dstABCD = _mm_loadu_si128((__m128i*) dst);
__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
ALPHA_BLEND_2();
*(uint64*) dst = EXTR64(srcABCD, 0);
_mm_storel_epi64((__m128i*) dst, srcABCD);
src += 2;
dst += 2;
}
if (bt_last == BT_ODD) {
__m128i srcABCD = _mm_loadu_si128((const __m128i*) src);
__m128i dstABCD = _mm_loadu_si128((__m128i*) dst);
__m128i srcABCD = _mm_cvtsi32_si128(src->data);
__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
ALPHA_BLEND_2();
(*dst).data = EXTR32(srcABCD, 0);
dst->data = _mm_cvtsi128_si32(srcABCD);
}
break;
}
@@ -99,8 +99,8 @@ inline void Blitter_32bppSSE2::Draw(const Blitter::BlitterParams *bp, ZoomLevel
const int width_diff = si->sprite_width - bp->width;
effective_width = bp->width - (int) src_rgba_line[0].data;
const int delta_diff = (int) src_rgba_line[1].data - width_diff;
const int nd = effective_width - delta_diff;
effective_width = delta_diff > 0 ? nd : effective_width;
const int new_width = effective_width - delta_diff;
effective_width = delta_diff > 0 ? new_width : effective_width;
if (effective_width <= 0) break;
/* FALLTHROUGH */
}
@@ -108,30 +108,28 @@ inline void Blitter_32bppSSE2::Draw(const Blitter::BlitterParams *bp, ZoomLevel
case RM_WITH_SKIP: {
const byte *remap = bp->remap;
for (uint x = (uint) effective_width; x != 0; x--) {
/* In case the m-channel is zero, do not remap this pixel in any way */
if (src_mv->m == 0) {
if (src->a < 255) {
__m128i srcABCD = _mm_loadu_si128((const __m128i*) src);
__m128i dstABCD = _mm_loadu_si128((__m128i*) dst);
ALPHA_BLEND_2();
(*dst).data = EXTR32(srcABCD, 0);
} else {
*dst = src->data;
}
} else {
/* In case the m-channel is zero, do not remap this pixel in any way. */
__m128i srcABCD;
if (src_mv->m) {
const uint r = remap[src_mv->m];
if (r != 0) {
Colour remapped_colour = AdjustBrightness(this->LookupColourInPalette(r), src_mv->v);
if (src->a < 255) {
__m128i srcABCD;
__m128i dstABCD = _mm_loadu_si128((__m128i*) dst);
remapped_colour.a = src->a;
INSR32(remapped_colour.data, srcABCD, 0);
ALPHA_BLEND_2();
(*dst).data = EXTR32(srcABCD, 0);
} else
if (src->a == 255) {
*dst = remapped_colour;
} else {
remapped_colour.a = src->a;
srcABCD = _mm_cvtsi32_si128(remapped_colour.data);
goto bmcr_alpha_blend_single;
}
}
} else {
srcABCD = _mm_cvtsi32_si128(src->data);
if (src->a < 255) {
bmcr_alpha_blend_single:
__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
ALPHA_BLEND_2();
}
dst->data = _mm_cvtsi128_si32(srcABCD);
}
src_mv++;
dst++;
@@ -149,27 +147,25 @@ inline void Blitter_32bppSSE2::Draw(const Blitter::BlitterParams *bp, ZoomLevel
/* Make the current colour a bit more black, so it looks like this image is transparent.
* rgb = rgb * ((256/4) * 4 - (alpha/4)) / ((256/4) * 4)
*/
__m128i srcABCD = _mm_loadu_si128((const __m128i*) src);
__m128i dstABCD = _mm_loadu_si128((__m128i*) dst);
for (uint x = (uint) bp->width / 2; x > 0; x--) {
__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
__m128i srcAB = _mm_unpacklo_epi8(srcABCD, _mm_setzero_si128());
__m128i dstAB = _mm_unpacklo_epi8(dstABCD, _mm_setzero_si128());
__m128i dstCD = _mm_unpackhi_epi8(dstABCD, _mm_setzero_si128());
__m128i alphaAB = _mm_shufflelo_epi16(srcAB, 0x3F);
alphaAB = _mm_shufflehi_epi16(alphaAB, 0x3F);
alphaAB = _mm_srli_epi16(alphaAB, 2); // Reduce to 64 levels of shades so the max value fits in 16 bits.
__m128i nom = _mm_sub_epi16(tr_nom_base, alphaAB);
dstAB = _mm_mullo_epi16(dstAB, nom);
dstAB = _mm_srli_epi16(dstAB, 8);
dstAB = _mm_packus_epi16(dstAB, dstCD);
Colour *old_dst = dst;
dstAB = _mm_packus_epi16(dstAB, dstAB);
_mm_storel_epi64((__m128i *) dst, dstAB);
src += 2;
dst += 2;
dstABCD = _mm_loadu_si128((__m128i*) dst);
_mm_storeu_si128((__m128i *) old_dst, dstAB);
srcABCD = _mm_loadu_si128((const __m128i*) src);
}
if (bp->width & 1) {
__m128i srcABCD = _mm_cvtsi32_si128(src->data);
__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
__m128i srcAB = _mm_unpacklo_epi8(srcABCD, _mm_setzero_si128());
__m128i dstAB = _mm_unpacklo_epi8(dstABCD, _mm_setzero_si128());
__m128i alphaAB = _mm_shufflelo_epi16(srcAB, 0x3F);
@@ -179,7 +175,7 @@ inline void Blitter_32bppSSE2::Draw(const Blitter::BlitterParams *bp, ZoomLevel
dstAB = _mm_mullo_epi16(dstAB, nom);
dstAB = _mm_srli_epi16(dstAB, 8);
dstAB = _mm_packus_epi16(dstAB, dstAB);
(*dst).data = EXTR32(dstAB, 0);
dst->data = _mm_cvtsi128_si32(dstAB);
}
break;
}
@@ -345,7 +341,7 @@ inline Colour Blitter_32bppSSE2::AdjustBrightness(Colour colour, uint8 brightnes
IGNORE_UNINITIALIZED_WARNING_START
/* static */ Colour Blitter_32bppSSE2::ReallyAdjustBrightness(Colour colour, uint8 brightness)
{
ALIGN(16) uint64 c16 = colour.b | (uint64) colour.g << 16 | (uint64) colour.r << 32;
uint64 c16 = colour.b | (uint64) colour.g << 16 | (uint64) colour.r << 32;
c16 *= brightness;
uint64 c16_ob = c16; // Helps out of order execution.
c16 /= DEFAULT_BRIGHTNESS;
@@ -357,12 +353,20 @@ IGNORE_UNINITIALIZED_WARNING_START
const uint32 alpha32 = colour.data & 0xFF000000;
__m128i ret;
#ifdef _SQ64
ret = _mm_cvtsi64_si128(c16);
#else
INSR64(c16, ret, 0);
#endif
if (ob != 0) {
/* Reduce overbright strength. */
ob /= 2;
__m128i ob128;
#ifdef _SQ64
ob128 = _mm_cvtsi64_si128(ob | ob << 16 | ob << 32);
#else
INSR64(ob | ob << 16 | ob << 32, ob128, 0);
#endif
__m128i white = OVERBRIGHT_VALUE_MASK;
__m128i c128 = ret;
ret = _mm_subs_epu16(white, c128); /* PSUBUSW, (255 - rgb) */
@@ -372,7 +376,7 @@ IGNORE_UNINITIALIZED_WARNING_START
}
ret = _mm_packus_epi16(ret, ret); /* PACKUSWB, saturate and pack. */
return alpha32 | EXTR32(ret, 0);
return alpha32 | _mm_cvtsi128_si32(ret);
}
IGNORE_UNINITIALIZED_WARNING_STOP