[PATCH v2][gold] AArch64: Implement MOVW_UABS_* and MOVW_SABS_* relocations.

[Igor Kudrin <ikudrin at accesssoftek dot com>]

Hi Cary, Han,

Thank you very much for the review comments!

Here is an updated patch with the following changes:
* Rebased to the top.
* Changed "(uint64_t)1" to "1ULL".
* Added a comment for "Rvalue_bit_select_impl<0, 0>".
* Changed "rela_general<64>" to "rela_general<32>".

Best regards,
Igor Kudrin

---
gold/ChangeLog

	* aarch64-reloc-property.cc (Rvalue_bit_select_impl): New class.
	(rvalue_bit_select): Use Rvalue_bit_select_impl.
	* aarch64-reloc.def (MOVW_UABS_G0, MOVW_UABS_G0_NC, MOVW_UABS_G1,
	MOVW_UABS_G1_NC, MOVW_UABS_G2, MOVW_UABS_G2_NC, MOVW_UABS_G3,
	MOVW_SABS_G0, MOVW_SABS_G1, MOVW_SABS_G2): New relocations.
	* aarch64.cc (Target_aarch64::Scan::local): Add cases for new
	MOVW_UABS_* and MOVW_SABS_* relocations.
	(Target_aarch64::Scan::global): Likewise.
	(Target_aarch64::Relocate::relocate): Add cases and handlings
	for new MOVW_UABS_* and MOVW_SABS_* relocations.
	* testsuite/Makefile.am (aarch64_relocs): New test.
	* testsuite/Makefile.in: Regenerate.
	* testsuite/aarch64_globals.s: New test source file.
	* testsuite/aarch64_relocs.s: Likewise.
	* testsuite/aarch64_relocs.sh: New test script.

________________________________________
From: Han Shen <shenhan@google.com>
Sent: Wednesday, June 29, 2016 8:48 AM
To: Cary Coutant
Cc: Igor Kudrin; binutils@sourceware.org
Subject: Re: [PATCH][gold] AArch64: Implement MOVW_UABS_* and MOVW_SABS_* relocations.

Hi Igor, could you add comments to the specialization that L=U=0 means
no check, otherwise readers might mistake it for selecting LSB. (The
origin code should have added it.)

+class Rvalue_bit_select_impl<0, 0>
+{
+public:
+  static uint64_t
+  calc(uint64_t x)
+  {
+    return x;
+  }
+};

Also in the below segment - "rela_general<64>" should be
"rela_general<32>", cause we are patching a 32 bit mov insn.

+    case elfcpp::R_AARCH64_MOVW_UABS_G3:
+      reloc_status = Reloc::template rela_general<64>(
+ view, object, psymval, addend, reloc_property);
+      break;

Thanks,
Han

On Tue, Jun 28, 2016 at 3:18 PM, Cary Coutant <ccoutant@gmail.com> wrote:
> [+shenhan this time]
>
> On Tue, Jun 28, 2016 at 3:17 PM, Cary Coutant <ccoutant@gmail.com> wrote:
>>> This patch implements R_AARCH64_MOVW_UABS_G* and R_AARCH64_MOVW_SABS_G*
>>> relocations for AArch64 target.
>>>
>>> Best regards,
>>> Igor Kudrin
>>>
>>> ---
>>> gold/ChangeLog
>>>
>>>         * aarch64-reloc-property.cc (Rvalue_bit_select_impl): New class.
>>>         (rvalue_bit_select): Use Rvalue_bit_select_impl.
>>>         * aarch64-reloc.def (MOVW_UABS_G0, MOVW_UABS_G0_NC, MOVW_UABS_G1,
>>>         MOVW_UABS_G1_NC, MOVW_UABS_G2, MOVW_UABS_G2_NC, MOVW_UABS_G3,
>>>         MOVW_SABS_G0, MOVW_SABS_G1, MOVW_SABS_G2): New relocations.
>>>         * aarch64.cc (Target_aarch64::Scan::local): Add cases for new
>>>         MOVW_UABS_* and MOVW_SABS_* relocations.
>>>         (Target_aarch64::Scan::global): Likewise.
>>>         (Target_aarch64::Relocate::relocate): Add cases and handlings
>>>         for new MOVW_UABS_* and MOVW_SABS_* relocations.
>>>         * testsuite/Makefile.am (aarch64_relocs): New test.
>>>         * testsuite/Makefile.in: Regenerate.
>>>         * testsuite/aarch64_globals.s: New test source file.
>>>         * testsuite/aarch64_relocs.s: New test source file.
>>>         * testsuite/aarch64_relocs.sh: New test script.
>>
>> +  static uint64_t
>> +  calc(uint64_t x)
>> +  {
>> +    return (x & (((uint64_t)1 << (U+1)) - 1)) >> L;
>> +  }
>>
>> I know this was the same before your patch, but I'd prefer using
>> "1ULL" instead of the C-style cast.
>>
>> Han, can you take a look at this patch?
>>
>> -cary



--
Han Shen |  Software Engineer |  shenhan@google.com |  +1-650-440-3330

Attachment: gold-aarch64-movw-abs-relocs-2.patch.txt
Description: gold-aarch64-movw-abs-relocs-2.patch.txt