On 27 June 2017 at 16:55, Yvan Roux <yvan.r...@linaro.org> wrote:
> Hi
>
> On 27 June 2017 at 16:49, Wilco Dijkstra <wilco.dijks...@arm.com> wrote:
>> As described in PR79041, -mcmodel=large -mpc-relative-literal-loads
>> may be used to avoid generating ADRP/ADD or ADRP/LDR. However both
>> trunk and GCC7 may still emit ADRP for some constant pool literals.
>> Fix this by adding a aarch64_pcrelative_literal_loads check.
>>
>> OK for trunk/GCC7 backport?
>
> I can't approve it, but the patch is ok for me, I've built and
> regtested the very same patch for aarch64-linux-gnu,
> aarch64-none-elf and aarch64_be-none-elf targets :)
>
> Yvan
>
>> ChangeLog:
>> 2017-06-27 Wilco Dijkstra <wdijk...@arm.com>
>>
>> PR target/79041
>> * config/aarch64/aarch64.c (aarch64_classify_symbol):
>> Avoid SYMBOL_SMALL_ABSOLUTE .
>> * testsuite/gcc.target/aarch64/pr79041-2.c: New test.
>> --
>> diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
>> index
>> 060cd8476d2954119daac495ecb059c9be73edbe..329d244e9cf16dbdf849e5dd02b3999caf0cd5a7
>> 100644
>> --- a/gcc/config/aarch64/aarch64.c
>> +++ b/gcc/config/aarch64/aarch64.c
>> @@ -10042,7 +10042,7 @@ aarch64_classify_symbol (rtx x, rtx offset)
>> /* This is alright even in PIC code as the constant
>> pool reference is always PC relative and within
>> the same translation unit. */
>> - if (CONSTANT_POOL_ADDRESS_P (x))
>> + if (CONSTANT_POOL_ADDRESS_P (x) &&
>> !aarch64_pcrelative_literal_loads)
maybe just a small note here, in my backport patch on gcc-6-branch a
kept the existing order in the condition:
- if (nopcrelative_literal_loads
+ if (!aarch64_pcrelative_literal_loads
&& CONSTANT_POOL_ADDRESS_P (x))
Can we keep it, or maybe I should wait for your patch to be committed
on trunk, and include its backport in my patch for GCC 6.
>> return SYMBOL_SMALL_ABSOLUTE;
>> else
>> return SYMBOL_FORCE_TO_MEM;
>> diff --git a/gcc/testsuite/gcc.target/aarch64/pr79041-2.c
>> b/gcc/testsuite/gcc.target/aarch64/pr79041-2.c
>> new file mode 100644
>> index
>> 0000000000000000000000000000000000000000..e7899725bad2b770f8488a07f99792113275bdf2
>> --- /dev/null
>> +++ b/gcc/testsuite/gcc.target/aarch64/pr79041-2.c
>> @@ -0,0 +1,10 @@
>> +/* { dg-do compile } */
>> +/* { dg-options "-O2 -mcmodel=large -mpc-relative-literal-loads" } */
>> +
>> +__int128
>> +t (void)
>> +{
>> + return (__int128)1 << 80;
>> +}
>> +
>> +/* { dg-final { scan-assembler "adr" } } */
