re PR target/44606 (Wrong SPE floating point during computation)

gcc/
        PR target/44606
        * reload1.c (choose_reload_regs): Don't look for equivalences for
        output reloads of constant loads.

gcc/testsuite/
        PR target/44606
        * gcc.dg/pr44606.c: New test.

From-SVN: r168347

gcc/ChangeLog

+2010-12-30  Nathan Froyd  <froydnj@codesourcery.com>
+
+        PR target/44606
+        * reload1.c (choose_reload_regs): Don't look for equivalences for
+        output reloads of constant loads.
+
 2010-12-30  Ulrich Weigand  <Ulrich.Weigand@de.ibm.com>
 
 	* emit-rtl.c (set_mem_attributes_minus_bitpos): Explicitly derive

gcc/reload1.c

@@ -6600,17 +6600,6 @@ choose_reload_regs (struct insn_chain *chain)
 	      && (rld[r].nregs == max_group_size
 		  || ! reg_classes_intersect_p (rld[r].rclass, group_class)))
 	    search_equiv = rld[r].in;
-	  /* If this is an output reload from a simple move insn, look
-	     if an equivalence for the input is available.  */
-	  else if (inheritance && rld[r].in == 0 && rld[r].out != 0)
-	    {
-	      rtx set = single_set (insn);
-
-	      if (set
-		  && rtx_equal_p (rld[r].out, SET_DEST (set))
-		  && CONSTANT_P (SET_SRC (set)))
-		search_equiv = SET_SRC (set);
-	    }
 
 	  if (search_equiv)
 	    {

gcc/testsuite/ChangeLog

+2010-12-30  Nathan Froyd  <froydnj@codesourcery.com>
+
+        PR target/44606
+        * gcc.dg/pr44606.c: New test.
+
 2010-12-30  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR target/46519

gcc/testsuite/gcc.dg/pr44606.c

+/* PR target/44606 */
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+#include <stdio.h>
+
+extern void abort (void);
+
+ typedef struct _PixelPacket { 	unsigned char r, g, b; }
+ PixelPacket;
+#define ARRAYLEN(X) (sizeof(X)/sizeof(X[0]))
+PixelPacket q[6];
+#define COLS (ARRAYLEN(q) - 1)
+PixelPacket p[2*COLS + 22];
+#define Minify(POS, WEIGHT) do {	\
+	total_r += (WEIGHT)*(p[POS].r);	\
+	total_g += (WEIGHT)*(p[POS].g);	\
+	total_b += (WEIGHT)*(p[POS].b);	\
+} while (0)
+unsigned long columns = COLS;
+int main(void)
+{
+	static const unsigned char answers[COLS] = { 31, 32, 34, 35, 36 };
+	unsigned long x;
+	for (x = 0; x < sizeof(p)/sizeof(p[0]); x++) {
+		p[x].b = (x + 34) | 1;
+	}
+	for (x = 0; x < columns; x++) {
+		double total_r = 0, total_g = 0, total_b = 0;
+		double saved_r = 0, saved_g = 0, saved_b = 0;
+		Minify(2*x +  0,  3.0);
+		Minify(2*x +  1,  7.0);
+		Minify(2*x +  2,  7.0);
+		saved_r = total_r;
+		saved_g = total_g;
+		Minify(2*x + 11, 15.0);
+		Minify(2*x + 12,  7.0);
+		Minify(2*x + 18,  7.0);
+		Minify(2*x + 19, 15.0);
+		Minify(2*x + 20, 15.0);
+		Minify(2*x + 21,  7.0);
+		q[x].r = (unsigned char)(total_r/128.0 + 0.5);
+		q[x].g = (unsigned char)(total_g/128.0 + 0.5);
+		q[x].b = (unsigned char)(total_b/128.0 + 0.5);
+		fprintf(stderr, "r:%f g:%f b:%f\n", saved_r, saved_g, saved_b);
+	}
+	for (x = 0; x < COLS; x++) {
+		if (answers[x] != q[x].b)
+			abort();
+	}
+	return 0;
+}