Make sure the work space memory is properly aligned

We use the heap allocators to avoid having more than one implementation
of the alignment logic.


git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@19 632fc199-4ca6-4c93-a231-07263d6284db

jcdctmgr.c

@@ -53,12 +53,16 @@ typedef struct {
    */
   DCTELEM * divisors[NUM_QUANT_TBLS];
 
+  /* work area for FDCT subroutine */
+  DCTELEM * workspace;
+
 #ifdef DCT_FLOAT_SUPPORTED
   /* Same as above for the floating-point case. */
   float_DCT_method_ptr float_dct;
   float_convsamp_method_ptr float_convsamp;
   float_quantize_method_ptr float_quantize;
   FAST_FLOAT * float_divisors[NUM_QUANT_TBLS];
+  FAST_FLOAT * float_workspace;
 #endif
 } my_fdct_controller;
 
@@ -403,10 +407,11 @@ forward_DCT (j_compress_ptr cinfo, jpeg_component_info * compptr,
   /* This routine is heavily used, so it's worth coding it tightly. */
   my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;
   DCTELEM * divisors = fdct->divisors[compptr->quant_tbl_no];
-  DCTELEM workspace[DCTSIZE2];	/* work area for FDCT subroutine */
+  DCTELEM * workspace;
   JDIMENSION bi;
 
   /* Make sure the compiler doesn't look up these every pass */
+  workspace = fdct->workspace;
   forward_DCT_method_ptr do_dct = fdct->dct;
   convsamp_method_ptr do_convsamp = fdct->convsamp;
   quantize_method_ptr do_quantize = fdct->quantize;
@@ -492,10 +497,12 @@ forward_DCT_float (j_compress_ptr cinfo, jpeg_component_info * compptr,
   /* This routine is heavily used, so it's worth coding it tightly. */
   my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;
   FAST_FLOAT * divisors = fdct->float_divisors[compptr->quant_tbl_no];
-  FAST_FLOAT workspace[DCTSIZE2]; /* work area for FDCT subroutine */
+  FAST_FLOAT * workspace;
   JDIMENSION bi;
 
+
   /* Make sure the compiler doesn't look up these every pass */
+  workspace = fdct->float_workspace;
   float_DCT_method_ptr do_dct = fdct->float_dct;
   float_convsamp_method_ptr do_convsamp = fdct->float_convsamp;
   float_quantize_method_ptr do_quantize = fdct->float_quantize;
@@ -603,6 +610,18 @@ jinit_forward_dct (j_compress_ptr cinfo)
     break;
   }
 
+  /* Allocate workspace memory */
+#ifdef DCT_FLOAT_SUPPORTED
+  if (cinfo->dct_method == JDCT_FLOAT)
+    fdct->float_workspace = (FAST_FLOAT *)
+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+				  SIZEOF(FAST_FLOAT) * DCTSIZE2);
+  else
+#endif
+    fdct->workspace = (DCTELEM *)
+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+				  SIZEOF(DCTELEM) * DCTSIZE2);
+
   /* Mark divisor tables unallocated */
   for (i = 0; i < NUM_QUANT_TBLS; i++) {
     fdct->divisors[i] = NULL;

jdcoefct.c

@@ -47,6 +47,9 @@ typedef struct {
    */
   JBLOCKROW MCU_buffer[D_MAX_BLOCKS_IN_MCU];
 
+  /* Temporary workspace for one MCU */
+  JCOEF * workspace;
+
 #ifdef D_MULTISCAN_FILES_SUPPORTED
   /* In multi-pass modes, we need a virtual block array for each component. */
   jvirt_barray_ptr whole_image[MAX_COMPONENTS];
@@ -471,13 +474,16 @@ decompress_smooth_data (j_decompress_ptr cinfo, JSAMPIMAGE output_buf)
   jpeg_component_info *compptr;
   inverse_DCT_method_ptr inverse_DCT;
   boolean first_row, last_row;
-  JBLOCK workspace;
+  JCOEF * workspace;
   int *coef_bits;
   JQUANT_TBL *quanttbl;
   INT32 Q00,Q01,Q02,Q10,Q11,Q20, num;
   int DC1,DC2,DC3,DC4,DC5,DC6,DC7,DC8,DC9;
   int Al, pred;
 
+  /* Keep a local variable to avoid looking it up more than once */
+  workspace = coef->workspace;
+
   /* Force some input to be done if we are getting ahead of the input. */
   while (cinfo->input_scan_number <= cinfo->output_scan_number &&
 	 ! cinfo->inputctl->eoi_reached) {
@@ -733,4 +739,9 @@ jinit_d_coef_controller (j_decompress_ptr cinfo, boolean need_full_buffer)
     coef->pub.decompress_data = decompress_onepass;
     coef->pub.coef_arrays = NULL; /* flag for no virtual arrays */
   }
+
+  /* Allocate the workspace buffer */
+  coef->workspace = (JCOEF *)
+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+                                SIZEOF(JCOEF) * DCTSIZE2);
 }