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Add a "colocated" flag to symbol references. (#298)

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This adds a "colocated" flag to function and symbolic global variables which
indicates that they are defined along with the current function, so they can
use PC-relative addressing.

This also changes the function decl syntax; the name now always precedes the
signature, and the "function" keyword is no longer included.
This commit is contained in:
Dan Gohman
2018-04-13 15:00:09 -07:00
committed by GitHub
parent 645fa3e858
commit 0e57f3d0ea
46 changed files with 312 additions and 164 deletions
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25
lib/cretonne/meta/isa/x86/encodings.py
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@@ -3,8 +3,9 @@ x86 Encodings.
"""
from __future__ import absolute_import
from cdsl.predicates import IsUnsignedInt, Not, And
from base.predicates import IsColocatedFunc, IsColocatedData
from base import instructions as base
from base.formats import UnaryImm
from base.formats import UnaryImm, FuncAddr, Call
from .defs import X86_64, X86_32
from . import recipes as r
from . import settings as cfg
@@ -292,16 +293,22 @@ enc_both(base.regspill.f64, r.fregspill32, 0xf2, 0x0f, 0x11)
# Function addresses.
#
# Non-PIC, all-ones funcaddresses.
X86_32.enc(base.func_addr.i32, *r.fnaddr4(0xb8),
isap=And(Not(allones_funcaddrs), Not(is_pic)))
X86_64.enc(base.func_addr.i64, *r.fnaddr8.rex(0xb8, w=1),
isap=And(Not(allones_funcaddrs), Not(is_pic)))
# Non-PIC, all-zeros funcaddresses.
X86_32.enc(base.func_addr.i32, *r.allones_fnaddr4(0xb8),
isap=And(allones_funcaddrs, Not(is_pic)))
X86_64.enc(base.func_addr.i64, *r.allones_fnaddr8.rex(0xb8, w=1),
isap=And(allones_funcaddrs, Not(is_pic)))
# PIC
X86_64.enc(base.func_addr.i64, *r.pcrel_fnaddr8.rex(0x8d, w=1),
isap=is_pic,
instp=IsColocatedFunc(FuncAddr.func_ref))
X86_64.enc(base.func_addr.i64, *r.got_fnaddr8.rex(0x8b, w=1),
isap=is_pic)
@@ -309,18 +316,34 @@ X86_64.enc(base.func_addr.i64, *r.got_fnaddr8.rex(0x8b, w=1),
# Global addresses.
#
# Non-PIC
X86_32.enc(base.globalsym_addr.i32, *r.gvaddr4(0xb8),
isap=Not(is_pic))
X86_64.enc(base.globalsym_addr.i64, *r.gvaddr8.rex(0xb8, w=1),
isap=Not(is_pic))
# PIC, colocated
X86_64.enc(base.globalsym_addr.i64, *r.pcrel_gvaddr8.rex(0x8d, w=1),
isap=is_pic,
instp=IsColocatedData())
# PIC, non-colocated
X86_64.enc(base.globalsym_addr.i64, *r.got_gvaddr8.rex(0x8b, w=1),
isap=is_pic)
#
# Call/return
#
# 32-bit, both PIC and non-PIC.
X86_32.enc(base.call, *r.call_id(0xe8))
# 64-bit, PIC, colocated and non-colocated. There is no 64-bit non-PIC, since
# non-PIC is currently using the large model, which requires calls be lowered
# to func_addr+call_indirect.
X86_64.enc(base.call, *r.call_id(0xe8),
isap=is_pic,
instp=IsColocatedFunc(Call.func_ref))
X86_64.enc(base.call, *r.call_plt_id(0xe8), isap=is_pic)
X86_32.enc(base.call_indirect.i32, *r.call_r(0xff, rrr=2))