[patch] A patch to Eterm's MMX extensions for 24 bit color

shade_24_mmx.patch (text/plain), 1.88 KB, created by Tres 'RiverRat' Melton on 2005-04-23 03:24:12 UTC

--- Eterm-0.9.3-orig/src/mmx_cmod.S	2004-01-11 15:13:02.000000000 -0700
+++ Eterm-0.9.3/src/mmx_cmod.S	2005-04-23 04:06:31.000000000 -0600
@@ -45,6 +45,8 @@
         .type shade_ximage_16_mmx,@function
 .global shade_ximage_32_mmx
         .type shade_ximage_32_mmx,@function
+.global shade_ximage_24_mmx
+        .type shade_ximage_24_mmx,@function
 
 .bss
 .text
@@ -483,4 +485,54 @@
 3:
         LEAVE
 
+
+shade_ximage_24_mmx:
+        ENTER
+
+        leal (%esi, %ebx, 3), %esi
+        negl %ebx
+        jz 3f
+
+        movd rm, %mm4
+        movd gm, %mm5
+        movd bm, %mm6
+        psllq $32, %mm4
+        psllq $16, %mm5
+        por %mm6, %mm4
+        por %mm5, %mm4
+
+        pcmpeqw %mm6, %mm6
+        psllw $15, %mm6                 /* 80 00 80 00 80 00 80 00 */
+        movq %mm6, %mm5
+        pmulhw %mm4, %mm5               /* Get correction factor */
+1:
+        movl %ebx, %ecx
+2:
+        movd (%esi, %ecx, 3), %mm1      /* 00 rr gg bb */
+        movd %mm1, %mm2			/* we need 8 bits of this later */
+        pxor %mm0, %mm0
+        punpcklbw %mm1, %mm0            /* 00 00 rr 00 gg 00 bb 00 */
+        pxor %mm6, %mm0                 /* Flip sign */
+
+        pmulhw %mm4, %mm0               /* 00 00 xx rr xx gg xx bb */
+        psubw %mm5, %mm0                /* Correct range */
+        packuswb %mm0, %mm0             /* 00 rr gg bb 00 rr gg bb */
+
+        pand 0xFF000000, %mm2		/* FF 00 00 00 */
+        por %mm2, %mm0			/* 8 old bits + 24 new ones */
+
+        movd %mm0, (%esi, %ecx, 3)	/* This will be fine as long as nothing jacks with the  */
+					/*   byte following the imagemap in memory between the  */
+					/*   time it was read and now (only for the last pixel) */
+					/* Eterm is not threaded so no problem */
+        incl %ecx
+        jnz 2b
+
+        addl bpl, %esi
+        decl %edx
+        jnz 1b
+3:
+        LEAVE
+
+
 #endif /* HAVE_MMX */