asan.c (asan_emit_stack_protection): Use full-sized mask to align the base…

asan.c (asan_emit_stack_protection): Use full-sized mask to align the base address on 64-bit strict-alignment platforms.

	* asan.c (asan_emit_stack_protection): Use full-sized mask to align
	the base address on 64-bit strict-alignment platforms.

From-SVN: r268949

gcc/ChangeLog

+2019-02-15  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* asan.c (asan_emit_stack_protection): Use full-sized mask to align
+	the base address on 64-bit strict-alignment platforms.
+
 2019-02-15  H.J. Lu  <hongjiu.lu@intel.com>
 
-	* config/i386/i386.h (VALID_MMX_REG_MODE): Correct the misplaced
-	')'.
+	* config/i386/i386.h (VALID_MMX_REG_MODE): Correct the misplaced ')'.
 
 2019-02-15  Uroš Bizjak  <ubizjak@gmail.com>
 

gcc/asan.c

@@ -1440,13 +1440,15 @@ asan_emit_stack_protection (rtx base, rtx pbase, unsigned int alignb,
 	base_align_bias = ((asan_frame_size + alignb - 1)
 			   & ~(alignb - HOST_WIDE_INT_1)) - asan_frame_size;
     }
+
   /* Align base if target is STRICT_ALIGNMENT.  */
   if (STRICT_ALIGNMENT)
-    base = expand_binop (Pmode, and_optab, base,
-			 gen_int_mode (-((GET_MODE_ALIGNMENT (SImode)
-					  << ASAN_SHADOW_SHIFT)
-					 / BITS_PER_UNIT), Pmode), NULL_RTX,
-			 1, OPTAB_DIRECT);
+    {
+      const HOST_WIDE_INT align
+	= (GET_MODE_ALIGNMENT (SImode) / BITS_PER_UNIT) << ASAN_SHADOW_SHIFT;
+      base = expand_binop (Pmode, and_optab, base, gen_int_mode (-align, Pmode),
+			   NULL_RTX, 1, OPTAB_DIRECT);
+    }
 
   if (use_after_return_class == -1 && pbase)
     emit_move_insn (pbase, base);