AltiVec SIMD implementation of fast integer inverse DCT

git-svn-id: svn://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1445 632fc199-4ca6-4c93-a231-07263d6284db

simd/jsimd_powerpc.c

@@ -339,6 +339,17 @@ jsimd_can_idct_islow (void)
 GLOBAL(int)
 jsimd_can_idct_ifast (void)
 {
+  init_simd();
+
+  /* The code is optimised for these values only */
+  if (DCTSIZE != 8)
+    return 0;
+  if (sizeof(DCTELEM) != 2)
+    return 0;
+
+  if (simd_support & JSIMD_ALTIVEC)
+    return 1;
+
   return 0;
 }
 
@@ -360,6 +371,8 @@ jsimd_idct_ifast (j_decompress_ptr cinfo, jpeg_component_info * compptr,
                   JCOEFPTR coef_block, JSAMPARRAY output_buf,
                   JDIMENSION output_col)
 {
+  jsimd_idct_ifast_altivec(compptr->dct_table, coef_block, output_buf,
+                           output_col);
 }
 
 GLOBAL(void)