+/*
+ * $XConsortium: stipsparc.s,v 1.9 94/04/17 20:29:09 rws Exp $
+ *
+Copyright (c) 1990 X Consortium
+
+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, sublicense, 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 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 NONINFRINGEMENT. IN NO EVENT SHALL THE
+X CONSORTIUM 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.
+
+Except as contained in this notice, the name of the X Consortium shall not be
+used in advertising or otherwise to promote the sale, use or other dealings
+in this Software without prior written authorization from the X Consortium.
+ *
+ * Author: Keith Packard, MIT X Consortium
+ */
+
+/*
+ * SPARC assembly code for optimized text rendering.
+ *
+ * Other stippling could be done in assembly, but the payoff is
+ * not nearly as large. Mostly because large areas are heavily
+ * optimized already.
+ */
+
+/* not that I expect to ever see an LSB SPARC, but ... */
+#ifdef LITTLE_ENDIAN
+# define BitsR sll
+# define BitsL srl
+# define BO(o) o
+# define HO(o) o
+# define WO(o) o
+# define FourBits(dest,bits) and bits, 0xf, dest
+#else
+# define BitsR srl
+# define BitsL sll
+# define BO(o) 3-o
+# define HO(o) 2-o
+# define WO(o) o
+# define FourBits(dest,bits) srl bits, 28, dest
+#endif
+
+/*
+ * cfbStippleStack(addr, stipple, value, stride, Count, Shift)
+ * 4 5 6 7 16(sp) 20(sp)
+ *
+ * Apply successive 32-bit stipples starting at addr, addr+stride, ...
+ *
+ * Used for text rendering, but only when no data could be lost
+ * when the stipple is shifted left by Shift bits
+ */
+/* arguments */
+#define addr %i0
+#define stipple %i1
+#define value %i2
+#define stride %i3
+#define count %i4
+#define shift %i5
+
+/* local variables */
+#define atemp %l0
+#define bits %l1
+#define lshift %l2
+#define sbase %l3
+#define stemp %l4
+
+#define CASE_SIZE 5 /* case blocks are 2^5 bytes each */
+#define CASE_MASK 0x1e0 /* first case mask */
+
+#define ForEachLine LY1
+#define NextLine LY2
+#define CaseBegin LY3
+#define ForEachBits LY4
+#define NextBits LY5
+
+#if defined(SVR4) || (defined(linux) && (defined(sparc) || defined(__sparc__)))
+#ifdef TETEXT
+#define _cfbStippleStack cfbStippleStackTE
+#else
+#define _cfbStippleStack cfbStippleStack
+#endif
+#else
+#ifdef TETEXT
+#define _cfbStippleStack _cfbStippleStackTE
+#endif
+#endif
+ .seg "text"
+ .proc 16
+ .globl _cfbStippleStack
+_cfbStippleStack:
+ save %sp,-64,%sp
+ sethi %hi(CaseBegin),sbase /* load up switch table */
+ or sbase,%lo(CaseBegin),sbase
+
+ mov 4,lshift /* compute offset within */
+ sub lshift, shift, lshift /* stipple of remaining bits */
+#ifdef LITTLE_ENDIAN
+ inc CASE_SIZE, shift /* first shift for LSB */
+#else
+ inc 28-CASE_SIZE, shift /* first shift for MSB */
+#endif
+ /* do ... while (--count > 0); */
+ForEachLine:
+ ld [stipple],bits /* get stipple bits */
+ mov addr,atemp /* set up for this line */
+#ifdef TETEXT
+ /* Terminal emulator fonts are expanded and have many 0 rows */
+ tst bits
+ bz NextLine /* skip out early on 0 */
+#endif
+ add addr, stride, addr /* step for the loop */
+ BitsR bits, shift, stemp /* get first bits */
+ and stemp, CASE_MASK, stemp /* compute first jump */
+ BitsL bits, lshift, bits /* set remaining bits */
+ jmp sbase+stemp /* ... */
+ tst bits
+
+ForEachBits:
+ inc 4, atemp
+ForEachBits1:
+ FourBits(stemp, bits) /* compute jump for */
+ sll stemp, CASE_SIZE, stemp /* these four bits */
+ BitsL bits, 4, bits /* step for remaining bits */
+ jmp sbase+stemp /* jump */
+ tst bits
+CaseBegin:
+ bnz,a ForEachBits1 /* 0 */
+ inc 4, atemp
+NextLine:
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+ nop
+
+ bnz ForEachBits /* 1 */
+ stb value, [atemp+BO(0)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+ nop
+
+ bnz ForEachBits /* 2 */
+ stb value, [atemp+BO(1)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+ nop
+
+ bnz ForEachBits /* 3 */
+ sth value, [atemp+HO(0)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+ nop
+
+ bnz ForEachBits /* 4 */
+ stb value, [atemp+BO(2)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+ nop
+
+ stb value, [atemp+BO(0)] /* 5 */
+ bnz ForEachBits
+ stb value, [atemp+BO(2)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+
+ stb value, [atemp+BO(1)] /* 6 */
+ bnz ForEachBits
+ stb value, [atemp+BO(2)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+
+ sth value, [atemp+HO(0)] /* 7 */
+ bnz ForEachBits
+ stb value, [atemp+BO(2)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+
+ bnz ForEachBits /* 8 */
+ stb value, [atemp+BO(3)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+ nop
+
+ stb value, [atemp+BO(0)] /* 9 */
+ bnz ForEachBits
+ stb value, [atemp+BO(3)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+
+ stb value, [atemp+BO(1)] /* a */
+ bnz ForEachBits
+ stb value, [atemp+BO(3)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+
+ sth value, [atemp+HO(0)] /* b */
+ bnz ForEachBits
+ stb value, [atemp+BO(3)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+
+ bnz ForEachBits /* c */
+ sth value, [atemp+HO(2)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+ nop
+
+ stb value, [atemp+BO(0)] /* d */
+ bnz ForEachBits
+ sth value, [atemp+HO(2)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+
+ stb value, [atemp+BO(1)] /* e */
+ bnz ForEachBits
+ sth value, [atemp+HO(2)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore
+
+ bnz ForEachBits /* f */
+ st value, [atemp+WO(0)]
+ deccc 1, count
+ bnz,a ForEachLine
+ inc 4, stipple
+ ret
+ restore