On 27/02/14 22:32, Marcus Shawcroft wrote:
> On 21 February 2014 04:24, Kugan <[email protected]> wrote:
>
>> Compiling inline asm results in ICE (PR60034). Alignment calculation in
>> aarch64_classify_address for (symbol_ref:DI ("*.LANCHOR4") [flags
>> 0x182])) seems wrong here.
>
> Hi Kugan,
>
> + else if (SYMBOL_REF_FLAGS (sym))
> + align = GET_MODE_ALIGNMENT (GET_MODE (sym));
>
> This is inserted into the LO_SUM handling in the function
> aarch64_classify_address(), the code in question is checking the
> alignment of the object to ensure that a scaled address instruction
> would be valid. The proposed code is testing if any of a bunch of
> unrelated predicate flags have been set on the symbol and using that
> to gate whether GET_MODE_ALIGNMENT would give accurate alignment
> information on the symbol. I'm not convinced that the presence of
> SYMBOL_REF_FLAGS states anything definitive about the relevance of
> GET_MODE_ALIGNMENT. The test looks like it fails because a section
> anchor has been introduced and we fail to determine anything sensible
> about the alignment of a section anchor. How about this instead?
>
> if (SYMBOL_REF_BLOCK (sym))
> align = SYMBOL_REF_BLOCK (sym)->alignment;
>
Thanks Marcus for the explanation. I have now changed it based on this
and regression tested on qemu-aarch64 for aarch64-none-linux-gnu with no
new regressions.
Is this OK?
>>
>> Fixing this also caused a regression for pr38151.c, which is due to
>> complex type being allocated with wrong alignment. Attached patch fixes
>> these issues.
>
> It ~might~ be beneficial to increase data_alignment here as suggest
> for performance reasons, but the existing alignment should not cause
> breakage... this issue suggest to me that the SYMBOL_REF_FLAGS
> approach is at fault.
>
Removing this hunk. I will post it as a desperate patch after more analysis.
Thanks,
Kugan
gcc/
2014-03-03 Kugan Vivekanandarajah <[email protected]>
PR target/60034
* aarch64/aarch64.c (aarch64_classify_address): Fix alignment for
section anchor.
gcc/testsuite/
2014-03-03 Kugan Vivekanandarajah <[email protected]>
PR target/60034
* gcc.target/aarch64/pr60034.c: New file.
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 901ad3d..d2a9217 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -3199,6 +3199,10 @@ aarch64_classify_address (struct aarch64_address_info
*info,
}
else if (SYMBOL_REF_DECL (sym))
align = DECL_ALIGN (SYMBOL_REF_DECL (sym));
+ else if (SYMBOL_REF_HAS_BLOCK_INFO_P (sym)
+ && SYMBOL_REF_ANCHOR_P (sym)
+ && SYMBOL_REF_BLOCK (sym) != NULL)
+ align = SYMBOL_REF_BLOCK (sym)->alignment;
else
align = BITS_PER_UNIT;
diff --git a/gcc/testsuite/gcc.target/aarch64/pr60034.c
b/gcc/testsuite/gcc.target/aarch64/pr60034.c
index e69de29..d126779 100644
--- a/gcc/testsuite/gcc.target/aarch64/pr60034.c
+++ b/gcc/testsuite/gcc.target/aarch64/pr60034.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99 -fgnu89-inline -O -Wall -Winline -Wwrite-strings
-fmerge-all-constants -frounding-math -g -Wstrict-prototypes" } */
+
+static unsigned long global_max_fast;
+
+void __libc_mallopt (int param_number, int value)
+{
+ __asm__ __volatile__ ("# %[_SDT_A21]" :: [_SDT_A21] "nr" ((global_max_fast)));
+ global_max_fast = 1;
+}
