xtensa: align data naturally when optimizing for size

gcc for xtensa always aligns data at least to a word boundary, even when
it has smaller natural alignment. This results in unexpectedly high data
section sizes and unreasonable amount of wasted space when linking
objects compiled with -fdata-sections flag.

Align data naturally when optimization for size is enabled.

2015-02-22  Max Filippov  <jcmvbkbc@gmail.com>

gcc/
	* config/xtensa/xtensa.h (CONSTANT_ALIGNMENT, DATA_ALIGNMENT):
	use natural alignment when optimizing for size.

From-SVN: r220923

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 843716d..02e60b7 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2015-02-22  Max Filippov  <jcmvbkbc@gmail.com>
+
+       * config/xtensa/xtensa.h (CONSTANT_ALIGNMENT, DATA_ALIGNMENT):
+       use natural alignment when optimizing for size.
+
 2015-02-23  Kaz Kojima  <kkojima@gcc.gnu.org>
 
        PR target/65153

diff --git a/gcc/config/xtensa/xtensa.h b/gcc/config/xtensa/xtensa.h
index 0de072b..74ca240 100644 (file)
--- a/gcc/config/xtensa/xtensa.h
+++ b/gcc/config/xtensa/xtensa.h
@@ -174,7 +174,8 @@ extern unsigned xtensa_current_frame_size;
    constants to be word aligned so that 'strcpy' calls that copy
    constants can be done inline.  */
 #define CONSTANT_ALIGNMENT(EXP, ALIGN)                                 \
-  ((TREE_CODE (EXP) == STRING_CST || TREE_CODE (EXP) == CONSTRUCTOR)   \
+  (!optimize_size &&                                                   \
+   (TREE_CODE (EXP) == STRING_CST || TREE_CODE (EXP) == CONSTRUCTOR)   \
    && (ALIGN) < BITS_PER_WORD                                          \
        ? BITS_PER_WORD                                                 \
        : (ALIGN))
@@ -186,7 +187,7 @@ extern unsigned xtensa_current_frame_size;
    that copy constants to character arrays can be done inline.  */
 #undef DATA_ALIGNMENT
 #define DATA_ALIGNMENT(TYPE, ALIGN)                                    \
-  ((((ALIGN) < BITS_PER_WORD)                                          \
+  (!optimize_size && (((ALIGN) < BITS_PER_WORD)                                \
     && (TREE_CODE (TYPE) == ARRAY_TYPE                                 \
        || TREE_CODE (TYPE) == UNION_TYPE                               \
        || TREE_CODE (TYPE) == RECORD_TYPE)) ? BITS_PER_WORD : (ALIGN))