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#!/usr/bin/env python
from llvm.core import *
from llvm.passes import *
from llvm.ee import *
# A helper class.
class strstream(object):
def __init__(self, s):
self.s = s
def read(self):
return self.s
# Create a module.
asm = """
define i32 @test() nounwind {
ret i32 42
}
define i32 @test1() nounwind {
entry:
%tmp = alloca i32
store i32 42, i32* %tmp, align 4
%tmp1 = load i32* %tmp, align 4
%tmp2 = call i32 @test()
%tmp3 = load i32* %tmp, align 4
%tmp4 = load i32* %tmp, align 4
ret i32 %tmp1
}
define i32 @test2() nounwind {
entry:
%tmp = call i32 @test()
ret i32 %tmp
}
"""
m = Module.from_assembly(strstream(asm))
print "-"*72
print m
# Let's run a module-level inlining pass. First, create a pass manager.
pm = PassManager.new()
# Add the target data as the first "pass". This is mandatory.
pm.add( TargetData.new('') )
# Add the inlining pass.
pm.add( PASS_FUNCTION_INLINING )
# Run it!
pm.run(m)
# Done with the pass manager.
del pm
# Print the result. Note the change in @test2.
print "-"*72
print m
# Let's run a DCE pass on the the function 'test1' now. First create a
# function pass manager.
fpm = FunctionPassManager.new(m)
# Add the target data as first "pass". This is mandatory.
fpm.add( TargetData.new('') )
# Add a DCE pass
fpm.add( PASS_AGGRESSIVE_DCE )
# Run the pass on the function 'test1'
fpm.run( m.get_function_named('test1') )
# Print the result. Note the change in @test1.
print "-"*72
print m
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