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-rw-r--r--source/fitz/halftone.c139
1 files changed, 111 insertions, 28 deletions
diff --git a/source/fitz/halftone.c b/source/fitz/halftone.c
index 0a53fbb3..b74f4b59 100644
--- a/source/fitz/halftone.c
+++ b/source/fitz/halftone.c
@@ -148,10 +148,117 @@ static void make_ht_line(unsigned char *buf, fz_halftone *ht, int x, int y, int
}
/* Inner mono thresholding code */
-typedef void (threshold_fn)(unsigned char *ht_line, unsigned char *pixmap, unsigned char *out, int w);
+typedef void (threshold_fn)(const unsigned char *ht_line, const unsigned char *pixmap, unsigned char *out, int w);
-#if 1
-static void do_threshold_1(unsigned char *ht_line, unsigned char *pixmap, unsigned char *out, int w)
+#ifdef ARCH_ARM
+
+static void
+do_threshold_1(const unsigned char * restrict ht_line, const unsigned char * restrict pixmap, unsigned char *restrict out, int w)
+__attribute__((naked));
+
+static void
+do_threshold_1(const unsigned char * restrict ht_line, const unsigned char * restrict pixmap, unsigned char *restrict out, int w)
+{
+ asm volatile(
+ ENTER_ARM
+ // Store one more reg that required to keep double stack alignment
+ "stmfd r13!,{r4-r7,r9,r14} \n"
+ "@ r0 = ht_line \n"
+ "@ r1 = pixmap \n"
+ "@ r2 = out \n"
+ "@ r3 = w \n"
+ "subs r3, r3, #7 @ r3 = w -= 7 \n"
+ "blt 2f @ while (w > 0) { \n"
+ "1: \n"
+ "mov r14,#0 @ r14= h = 0 \n"
+ "ldrb r4, [r0], #1 @ r4 = ht_line[0] \n"
+ "ldrb r5, [r1], #2 @ r5 = pixmap[0] \n"
+ "ldrb r6, [r0], #1 @ r6 = ht_line[1] \n"
+ "ldrb r7, [r1], #2 @ r7 = pixmap[2] \n"
+ "cmp r5, r4 @ if (r5 < r4) \n"
+ "orrlt r14,r14,#0x80 @ h |= 0x80 \n"
+ "ldrb r4, [r0], #1 @ r4 = ht_line[2] \n"
+ "ldrb r5, [r1], #2 @ r5 = pixmap[4] \n"
+ "cmp r7, r6 @ if (r7 < r6) \n"
+ "orrlt r14,r14,#0x40 @ h |= 0x40 \n"
+ "ldrb r6, [r0], #1 @ r6 = ht_line[3] \n"
+ "ldrb r7, [r1], #2 @ r7 = pixmap[6] \n"
+ "cmp r5, r4 @ if (r5 < r4) \n"
+ "orrlt r14,r14,#0x20 @ h |= 0x20 \n"
+ "ldrb r4, [r0], #1 @ r4 = ht_line[2] \n"
+ "ldrb r5, [r1], #2 @ r5 = pixmap[4] \n"
+ "cmp r7, r6 @ if (r7 < r6) \n"
+ "orrlt r14,r14,#0x10 @ h |= 0x10 \n"
+ "ldrb r6, [r0], #1 @ r6 = ht_line[3] \n"
+ "ldrb r7, [r1], #2 @ r7 = pixmap[6] \n"
+ "cmp r5, r4 @ if (r5 < r4) \n"
+ "orrlt r14,r14,#0x08 @ h |= 0x08 \n"
+ "ldrb r4, [r0], #1 @ r4 = ht_line[2] \n"
+ "ldrb r5, [r1], #2 @ r5 = pixmap[4] \n"
+ "cmp r7, r6 @ if (r7 < r6) \n"
+ "orrlt r14,r14,#0x04 @ h |= 0x04 \n"
+ "ldrb r6, [r0], #1 @ r6 = ht_line[3] \n"
+ "ldrb r7, [r1], #2 @ r7 = pixmap[6] \n"
+ "cmp r5, r4 @ if (r5 < r4) \n"
+ "orrlt r14,r14,#0x02 @ h |= 0x02 \n"
+ "cmp r7, r6 @ if (r7 < r6) \n"
+ "orrlt r14,r14,#0x01 @ h |= 0x01 \n"
+ "subs r3, r3, #8 @ w -= 8 \n"
+ "strb r14,[r2], #1 @ *out++ = h \n"
+ "bgt 1b @ } \n"
+ "1: \n"
+ "adds r3, r3, #6 @ w += 6 \n"
+ "blt 3f @ if (w < 0) { \n"
+ "ldrb r4, [r0], #1 @ r4 = ht_line[0] \n"
+ "ldrb r5, [r1], #2 @ r5 = pixmap[0] \n"
+ "mov r14, #0 @ r14= h = 0 \n"
+ "cmp r5, r4 @ if (r5 < r4) \n"
+ "orrlt r14,r14,#0x80 @ h |= 0x80 \n"
+ "teq r3, #0 @ \n"
+ "ldrneb r4, [r0], #1 @ r6 = ht_line[1] \n"
+ "ldrneb r5, [r1], #2 @ r7 = pixmap[2] \n"
+ "beq 2f @ \n"
+ "cmp r5, r4 @ if (r5 < r4) \n"
+ "orrlt r14,r14,#0x40 @ h |= 0x40 \n"
+ "teq r3, #1 @ \n"
+ "ldrneb r4, [r0], #1 @ r6 = ht_line[1] \n"
+ "ldrneb r5, [r1], #2 @ r7 = pixmap[2] \n"
+ "beq 2f @ \n"
+ "cmp r5, r4 @ if (r5 < r4) \n"
+ "orrlt r14,r14,#0x20 @ h |= 0x20 \n"
+ "teq r3, #2 @ \n"
+ "ldrneb r4, [r0], #1 @ r6 = ht_line[1] \n"
+ "ldrneb r5, [r1], #2 @ r7 = pixmap[2] \n"
+ "beq 2f @ \n"
+ "cmp r5, r4 @ if (r5 < r4) \n"
+ "orrlt r14,r14,#0x10 @ h |= 0x10 \n"
+ "teq r3, #3 @ \n"
+ "ldrneb r4, [r0], #1 @ r6 = ht_line[1] \n"
+ "ldrneb r5, [r1], #2 @ r7 = pixmap[2] \n"
+ "beq 2f @ \n"
+ "cmp r5, r4 @ if (r5 < r4) \n"
+ "orrlt r14,r14,#0x08 @ h |= 0x08 \n"
+ "teq r3, #4 @ \n"
+ "ldrneb r4, [r0], #1 @ r6 = ht_line[1] \n"
+ "ldrneb r5, [r1], #2 @ r7 = pixmap[2] \n"
+ "beq 2f @ \n"
+ "cmp r5, r4 @ if (r5 < r4) \n"
+ "orrlt r14,r14,#0x04 @ h |= 0x04 \n"
+ "teq r3, #5 @ \n"
+ "ldrneb r4, [r0], #1 @ r6 = ht_line[1] \n"
+ "ldrneb r5, [r1], #2 @ r7 = pixmap[2] \n"
+ "beq 2f @ \n"
+ "cmp r5, r4 @ if (r5 < r4) \n"
+ "orrlt r14,r14,#0x02 @ h |= 0x02 \n"
+ "2: \n"
+ "strb r14,[r2] @ *out = h \n"
+ "3: \n"
+ "ldmfd r13!,{r4-r7,r9,PC} @ pop, return to thumb \n"
+ ENTER_THUMB
+ );
+}
+#else
+static void do_threshold_1(const unsigned char * restrict ht_line, const unsigned char * restrict pixmap, unsigned char * restrict out, int w)
{
int h;
@@ -200,30 +307,6 @@ static void do_threshold_1(unsigned char *ht_line, unsigned char *pixmap, unsign
*out++ = h;
}
}
-#else
-static void do_threshold_1(unsigned char *ht_line, unsigned char *pixmap, unsigned char *out, int w)
-{
- int bit = 0x80;
- int h = 0;
-
- do
- {
- if (*pixmap < *ht_line++)
- h |= bit;
- pixmap += 2; /* Skip the alpha */
- bit >>= 1;
- if (bit == 0)
- {
- *out++ = h;
- h = 0;
- bit = 0x80;
- }
-
- }
- while (--w);
- if (bit != 0x80)
- *out = h;
-}
#endif
/*
@@ -233,7 +316,7 @@ static void do_threshold_1(unsigned char *ht_line, unsigned char *pixmap, unsign
white = 0xFF. Reversing these tests enables us to maintain that
BlackIs1 in bitmaps.
*/
-static void do_threshold_4(unsigned char *ht_line, unsigned char *pixmap, unsigned char *out, int w)
+static void do_threshold_4(const unsigned char * restrict ht_line, const unsigned char * restrict pixmap, unsigned char * restrict out, int w)
{
w--;
while (w > 0)
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-23 18:34:21 +0000