From b2b9ee88ce9885af175cf7bd51898a6cfb519fe4 Mon Sep 17 00:00:00 2001
From: Martin Teichmann <martin.teichmann@xfel.eu>
Date: Thu, 24 Dec 2020 13:56:50 +0000
Subject: [PATCH] factor out at SimpleComparison
---
ebpf.py | 67 +++++++++++++++++++++++++++++++--------------------------
1 file changed, 36 insertions(+), 31 deletions(-)
diff --git a/ebpf.py b/ebpf.py
index a95d5d6..bd219c2 100644
--- a/ebpf.py
+++ b/ebpf.py
@@ -26,37 +26,12 @@ def comparison(uposop, unegop, sposop=None, snegop=None):
sposop = uposop
snegop = unegop
def ret(self, value):
- return Comparison(self.ebpf, self, value,
- (uposop, unegop, sposop, snegop))
+ return SimpleComparison(self.ebpf, self, value,
+ (uposop, unegop, sposop, snegop))
return ret
class Comparison:
- def __init__(self, ebpf, left, right, opcode):
- self.ebpf = ebpf
- self.left = left
- self.right = right
- self.opcode = opcode
- self.invert = None
-
- def compare(self, negative):
- self.dst, _, lsigned, lfree = self.left.calculate(None, None, None)
- if not isinstance(self.right, int):
- self.src, _, rsigned, rfree = \
- self.right.calculate(None, None, None)
- if rsigned != rsigned:
- raise AssembleError("need same signedness for comparison")
- else:
- rfree = False
- self.origin = len(self.ebpf.opcodes)
- self.ebpf.opcodes.append(None)
- self.opcode = self.opcode[negative + 2 * lsigned]
- if lfree:
- self.ebpf.owners.discard(self.dst)
- if rfree:
- self.ebpf.owners.discard(self.src)
- self.owners = self.ebpf.owners.copy()
-
def target(self):
assert self.ebpf.opcodes[self.origin] is None
if isinstance(self.right, int):
@@ -101,11 +76,41 @@ class Comparison:
return self
-class OrComparison(Comparison):
+class SimpleComparison(Comparison):
+ def __init__(self, ebpf, left, right, opcode):
+ self.ebpf = ebpf
+ self.left = left
+ self.right = right
+ self.opcode = opcode
+ self.invert = None
+
+ def compare(self, negative):
+ self.dst, _, lsigned, lfree = self.left.calculate(None, None, None)
+ if not isinstance(self.right, int):
+ self.src, _, rsigned, rfree = \
+ self.right.calculate(None, None, None)
+ if rsigned != rsigned:
+ raise AssembleError("need same signedness for comparison")
+ else:
+ rfree = False
+ self.origin = len(self.ebpf.opcodes)
+ self.ebpf.opcodes.append(None)
+ self.opcode = self.opcode[negative + 2 * lsigned]
+ if lfree:
+ self.ebpf.owners.discard(self.dst)
+ if rfree:
+ self.ebpf.owners.discard(self.src)
+ self.owners = self.ebpf.owners.copy()
+
+class AndOrComparison(Comparison):
def compare(self, negative):
self.left.compare(negative)
self.right.compare(negative)
+ def target(self):
+ self.left.target()
+ self.right.target()
+
def binary(opcode, symetric=False):
def ret(self, value):
@@ -186,13 +191,13 @@ class Sum(Binary):
return super().__sub__(value)
-class AndExpression(Binary, Comparison):
+class AndExpression(Binary, SimpleComparison):
__and__ = __rand__ = comparison(0x45, None)
__rand__ = __and__ = binary(0x54, True)
def __init__(self, ebpf, left, right):
Binary.__init__(self, ebpf, left, right, 0x54)
- Comparison.__init__(self, ebpf, left, right, 0x45)
+ SimpleComparison.__init__(self, ebpf, left, right, 0x45)
self.opcode = (0x45, None, 0x45, None)
def compare(self, negative):
@@ -392,7 +397,7 @@ class EBPF:
return comp
def jump(self):
- comp = Comparison(self, None, 0, 5)
+ comp = SimpleComparison(self, None, 0, 5)
comp.origin = len(self.opcodes)
comp.dst = 0
comp.owners = self.owners.copy()
--
GitLab