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From: Andreas Schwab <schwab@suse.de>
To: Daniel Kiper <dkiper@net-space.pl>
Cc: The development of GNU GRUB <grub-devel@gnu.org>,
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Subject: Re: [PATCH v3 07/10] RISC-V: Add awareness for RISC-V reloations
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	<20181121155157.xe2kahpmvia45rbu@tomti.i.net-space.pl>
X-Yow: Sign my PETITION.
Date: Wed, 21 Nov 2018 17:08:09 +0100
In-Reply-To: <20181121155157.xe2kahpmvia45rbu@tomti.i.net-space.pl> (Daniel
	Kiper's message of "Wed, 21 Nov 2018 16:51:57 +0100")
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On Nov 21 2018, Daniel Kiper <dkiper@net-space.pl> wrote:

>> +	case R_RISCV_BRANCH:
>> +	  {
>> +	    grub_uint32_t *abs_place = place;
>> +	    grub_ssize_t off = sym_addr - (grub_addr_t) place;
>> +	    grub_uint32_t imm12 = (off & 0x1000) << (31 - 12);
>> +	    grub_uint32_t imm11 = (off & 0x800) >> (11 - 7);
>> +	    grub_uint32_t imm10_5 = (off & 0x7e0) << (30 - 10);
>> +	    grub_uint32_t imm4_1 = (off & 0x1e) << (11 - 4);
>> +	    *abs_place = (*abs_place & 0x1fff07f)
>> +			 | imm12 | imm11 | imm10_5 | imm4_1;
>
> Could not we use some constants instead of numbers here?

These are just where the insn encoding puts the bits.

> If this does not make sense than please name the source of this numbers.

https://github.com/riscv/riscv-isa-manual/blob/master/release/riscv-spec-v2.2.pdf

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."