mips.c (mips_prepare_pch_save): Initialize micromips_globals to zero.

2016-10-13  Catherine Moore  <clm@codesourcery.com>

	* gcc/config/mips/mips.c (mips_prepare_pch_save): Initialize
	micromips_globals to zero.

From-SVN: r241165

gcc/ChangeLog

+2016-10-14  Catherine Moore  <clm@codesourcery.com>
+
+	* gcc/config/mips/mips.c (mips_prepare_pch_save): Initialize
+	micromips_globals to zero.
+
 2016-10-14  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/77979

gcc/config/mips/mips.c

@@ -20856,28 +20856,30 @@ mips_shift_truncation_mask (machine_mode mode)
 static void
 mips_prepare_pch_save (void)
 {
-  /* We are called in a context where the current MIPS16 vs. non-MIPS16
-     setting should be irrelevant.  The question then is: which setting
-     makes most sense at load time?
+  /* We are called in a context where the current compression vs.
+     non-compression setting should be irrelevant.  The question then is:
+     which setting makes most sense at load time?
 
-     The PCH is loaded before the first token is read.  We should never
-     have switched into MIPS16 mode by that point, and thus should not
-     have populated mips16_globals.  Nor can we load the entire contents
-     of mips16_globals from the PCH file, because mips16_globals contains
-     a combination of GGC and non-GGC data.
+     The PCH is loaded before the first token is read.  We should never have
+     switched into a compression mode by that point, and thus should not have
+     populated mips16_globals or micromips_globals.  Nor can we load the
+     entire contents of mips16_globals or micromips_globals from the PCH file,
+     because they contain a combination of GGC and non-GGC data.
 
      There is therefore no point in trying save the GGC part of
-     mips16_globals to the PCH file, or to preserve MIPS16ness across
-     the PCH save and load.  The loading compiler would not have access
-     to the non-GGC parts of mips16_globals (either from the PCH file,
-     or from a copy that the loading compiler generated itself) and would
-     have to call target_reinit anyway.
-
-     It therefore seems best to switch back to non-MIPS16 mode at
-     save time, and to ensure that mips16_globals remains null after
-     a PCH load.  */
+     mips16_globals/micromips_globals to the PCH file, or to preserve a
+     compression setting across the PCH save and load.  The loading compiler
+     would not have access to the non-GGC parts of mips16_globals or
+     micromips_globals (either from the PCH file, or from a copy that the
+     loading compiler generated itself) and would have to call target_reinit
+     anyway.
+
+     It therefore seems best to switch back to non-MIPS16 mode and
+     non-microMIPS mode to save time, and to ensure that mips16_globals and
+     micromips_globals remain null after a PCH load.  */
   mips_set_compression_mode (0);
   mips16_globals = 0;
+  micromips_globals = 0;
 }
 
 /* Generate or test for an insn that supports a constant permutation.  */