std/jpeg: tweak ignore too-short marker code
name old speed new speed delta
wuffs_jpeg_decode_19k_8bpp/clang14 317MB/s ± 0% 325MB/s ± 0% +2.60% (p=0.008 n=5+5)
wuffs_jpeg_decode_30k_24bpp_progressive/clang14 322MB/s ± 0% 325MB/s ± 0% +0.94% (p=0.008 n=5+5)
wuffs_jpeg_decode_30k_24bpp_sequential/clang14 864MB/s ± 0% 880MB/s ± 0% +1.84% (p=0.008 n=5+5)
wuffs_jpeg_decode_77k_24bpp/clang14 720MB/s ± 0% 730MB/s ± 0% +1.39% (p=0.016 n=4+5)
wuffs_jpeg_decode_552k_24bpp_420/clang14 783MB/s ± 0% 794MB/s ± 0% +1.44% (p=0.008 n=5+5)
wuffs_jpeg_decode_552k_24bpp_444/clang14 884MB/s ± 0% 914MB/s ± 0% +3.39% (p=0.008 n=5+5)
wuffs_jpeg_decode_4002k_24bpp/clang14 781MB/s ± 0% 796MB/s ± 0% +1.90% (p=0.008 n=5+5)
wuffs_jpeg_decode_19k_8bpp/gcc12 359MB/s ± 0% 360MB/s ± 0% +0.12% (p=0.008 n=5+5)
wuffs_jpeg_decode_30k_24bpp_progressive/gcc12 311MB/s ± 0% 310MB/s ± 0% -0.30% (p=0.008 n=5+5)
wuffs_jpeg_decode_30k_24bpp_sequential/gcc12 909MB/s ± 0% 915MB/s ± 0% +0.66% (p=0.008 n=5+5)
wuffs_jpeg_decode_77k_24bpp/gcc12 747MB/s ± 0% 750MB/s ± 0% +0.34% (p=0.008 n=5+5)
wuffs_jpeg_decode_552k_24bpp_420/gcc12 817MB/s ± 0% 819MB/s ± 0% +0.30% (p=0.008 n=5+5)
wuffs_jpeg_decode_552k_24bpp_444/gcc12 971MB/s ± 0% 972MB/s ± 0% +0.11% (p=0.008 n=5+5)
wuffs_jpeg_decode_4002k_24bpp/gcc12 819MB/s ± 0% 821MB/s ± 0% +0.21% (p=0.008 n=5+5)
diff --git a/release/c/wuffs-unsupported-snapshot.c b/release/c/wuffs-unsupported-snapshot.c
index 320e924..15cf5a3 100644
--- a/release/c/wuffs-unsupported-snapshot.c
+++ b/release/c/wuffs-unsupported-snapshot.c
@@ -49070,14 +49070,14 @@
}
self->private_impl.f_payload_length = t_4;
}
- if (self->private_impl.f_payload_length >= 2u) {
- self->private_impl.f_payload_length -= 2u;
- } else if ((v_marker == 254u) || ((224u <= v_marker) && (v_marker < 240u))) {
- continue;
- } else {
+ if (self->private_impl.f_payload_length < 2u) {
+ if ((v_marker == 254u) || ((224u <= v_marker) && (v_marker < 240u))) {
+ continue;
+ }
status = wuffs_base__make_status(wuffs_jpeg__error__bad_marker);
goto exit;
}
+ self->private_impl.f_payload_length -= 2u;
}
if (v_marker < 192u) {
status = wuffs_base__make_status(wuffs_jpeg__error__unsupported_marker);
diff --git a/std/jpeg/decode_jpeg.wuffs b/std/jpeg/decode_jpeg.wuffs
index 40ee683..5754195 100644
--- a/std/jpeg/decode_jpeg.wuffs
+++ b/std/jpeg/decode_jpeg.wuffs
@@ -426,18 +426,18 @@
} else {
this.payload_length = args.src.read_u16be_as_u32?()
// Payload length includes the 2 bytes for the u16be just read.
- if this.payload_length >= 2 {
- this.payload_length -= 2
- } else if (marker == 0xFE) or // COM.
- ((0xE0 <= marker) and (marker < 0xF0)) { // APPn.
- // Strictly speaking, this is invalid according to Section
- // B.1.1.4 "Marker segments". However, libjpeg-turbo allows it
- // (for COM and APPn markers; see its jdmarker.c file's
- // skip_variable function) so we do too.
- continue
- } else {
+ if this.payload_length < 2 {
+ if (marker == 0xFE) or // COM.
+ ((0xE0 <= marker) and (marker < 0xF0)) { // APPn.
+ // Strictly speaking, this is invalid according to Section
+ // B.1.1.4 "Marker segments". However, libjpeg-turbo allows
+ // it (for COM and APPn markers; see its jdmarker.c file's
+ // skip_variable function) so we do too.
+ continue
+ }
return "#bad marker"
}
+ this.payload_length -= 2
}
// Switch on the marker.
