re PR rtl-optimization/14235 (ICE in verify_local_live_at start (flow.c:546))

	PR optimization/14235
	* expr.c (convert_move): Copy the source to a new pseudo
	when converting from a sub-word source to a larger-than-word
	register which conflicts with the source.

From-SVN: r78893

gcc/ChangeLog

+2004-03-04  Eric Botcazou  <ebotcazou@libertysurf.fr>
+
+	PR optimization/14235
+	* expr.c (convert_move): Copy the source to a new pseudo
+	when converting from a sub-word source to a larger-than-word
+	register which conflicts with the source.
+
 2004-03-03  Zack Weinberg  <zack@codesourcery.com>
 
 	PR 13728

gcc/expr.c

@@ -682,7 +682,11 @@ convert_move (rtx to, rtx from, int unsignedp)
 		   != CODE_FOR_nothing))
 	{
 	  if (GET_CODE (to) == REG)
-	    emit_insn (gen_rtx_CLOBBER (VOIDmode, to));
+	    {
+	      if (reg_overlap_mentioned_p (to, from))
+		from = force_reg (from_mode, from);
+	      emit_insn (gen_rtx_CLOBBER (VOIDmode, to));
+	    }
 	  convert_move (gen_lowpart (word_mode, to), from, unsignedp);
 	  emit_unop_insn (code, to,
 			  gen_lowpart (word_mode, to), equiv_code);

gcc/testsuite/ChangeLog

+2004-03-04  Eric Botcazou  <ebotcazou@libertysurf.fr>
+
+	* gcc.c-torture/compile/20040304-1.c: New test.
+
 2004-03-03  Zack Weinberg  <zack@codesourcery.com>
 
 	PR 13728

gcc/testsuite/gcc.c-torture/compile/20040304-1.c

+/* PR optimization/14235 */
+/* Origin: <senor_fjord@yahoo.com> */
+
+typedef signed char        int8_t;
+typedef short              int16_t;
+typedef int                int32_t;
+typedef unsigned long long uint64_t;
+
+static const uint64_t LOW_BYTE_MASK    = 0x00000000000000ffULL;
+static const uint64_t HIGH_BYTE_MASK   = 0x000000000000ff00ULL;
+static const uint64_t WORD_MASK        = 0x000000000000ffffULL;
+static const uint64_t DWORD_MASK       = 0x00000000ffffffffULL;
+
+extern uint64_t *srca_mask;
+extern int *assert_thrown;
+
+void foo()
+{
+  uint64_t tempA = 0; /* actually a bunch of code to set A */ 
+  uint64_t tempB = 0; /* actually a bunch of code to set B */ 
+
+  /* cast A to right size */
+  tempA = (((*srca_mask == LOW_BYTE_MASK) || 
+            (*srca_mask == HIGH_BYTE_MASK)) ?
+           ((int8_t)tempA) : 
+           ((*srca_mask == WORD_MASK) ? 
+            ((int16_t)tempA) : 
+            ((*srca_mask == DWORD_MASK) ? 
+             ((int32_t)tempA) : 
+             tempA)));
+
+  /* cast B to right size */
+  tempB = (((*srca_mask == LOW_BYTE_MASK) || 
+            (*srca_mask == HIGH_BYTE_MASK)) ? 
+           ((int8_t)tempB) : 
+           ((*srca_mask == WORD_MASK) ? 
+            ((int16_t)tempB) : 
+            ((*srca_mask == DWORD_MASK) ? 
+             ((int32_t)tempB) : 
+             tempB))); 
+    
+  if ((int) tempA > (int) tempB) { 
+    *assert_thrown = 1;
+  }
+}