Add Om1 lowering with no optimizations

crosstest/crosstest.py

+#!/usr/bin/env python2
+
+import argparse
+import os
+import re
+import subprocess
+import sys
+import tempfile
+
+sys.path.insert(0, '../pydir')
+from utils import shellcmd
+
+if __name__ == '__main__':
+    """Builds a cross-test binary that allows functions translated by
+    Subzero and llc to be compared.
+
+    Each --test argument is compiled once by llc and once by Subzero.
+    C/C++ tests are first compiled down to PNaCl bitcode by the
+    build-pnacl-ir.py script.  The --prefix argument ensures that
+    symbol names are different between the two object files, to avoid
+    linking errors.
+
+    There is also a --driver argument that specifies the C/C++ file
+    that calls the test functions with a variety of interesting inputs
+    and compares their results.
+    """
+    # arch_map maps a Subzero target string to an llvm-mc -arch string.
+    arch_map = { 'x8632':'x86', 'x8664':'x86-64', 'arm':'arm' }
+    desc = 'Build a cross-test that compares Subzero and llc translation.'
+    argparser = argparse.ArgumentParser(description=desc)
+    argparser.add_argument('--test', required=True, action='append',
+                           metavar='TESTFILE_LIST',
+                           help='List of C/C++/.ll files with test functions')
+    argparser.add_argument('--driver', required=True,
+                           metavar='DRIVER',
+                           help='Driver program')
+    argparser.add_argument('--target', required=False, default='x8632',
+                           choices=arch_map.keys(),
+                           metavar='TARGET',
+                           help='Translation target architecture')
+    argparser.add_argument('-O', required=False, default='2', dest='optlevel',
+                           choices=['m1', '-1', '0', '1', '2'],
+                           metavar='OPTLEVEL',
+                           help='Optimization level ' +
+                                '(m1 and -1 are equivalent)')
+    argparser.add_argument('--prefix', required=True,
+                           metavar='SZ_PREFIX',
+                           help='String prepended to Subzero symbol names')
+    argparser.add_argument('--output', '-o', required=True,
+                           metavar='EXECUTABLE',
+                           help='Executable to produce')
+    argparser.add_argument('--dir', required=False, default='.',
+                           metavar='OUTPUT_DIR',
+                           help='Output directory for all files')
+    argparser.add_argument('--llvm-bin-path', required=False,
+                           default=os.environ.get('LLVM_BIN_PATH'),
+                           metavar='PATH',
+                           help='Path to LLVM executables like llc ' +
+                                '(defaults to $LLVM_BIN_PATH)')
+    args = argparser.parse_args()
+
+    objs = []
+    remove_internal = re.compile('^define internal ')
+    fix_target = re.compile('le32-unknown-nacl')
+    llvm_bin_path = args.llvm_bin_path
+    for arg in args.test:
+        base, ext = os.path.splitext(arg)
+        if ext == '.ll':
+            bitcode = arg
+        else:
+            bitcode = os.path.join(args.dir, base + '.pnacl.ll')
+            shellcmd(['../pydir/build-pnacl-ir.py', '--disable-verify',
+                      '--dir', args.dir, arg])
+            # Read in the bitcode file, fix it up, and rewrite the file.
+            f = open(bitcode)
+            ll_lines = f.readlines()
+            f.close()
+            f = open(bitcode, 'w')
+            for line in ll_lines:
+                line = remove_internal.sub('define ', line)
+                line = fix_target.sub('i686-pc-linux-gnu', line)
+                f.write(line)
+            f.close()
+
+        asm_sz = os.path.join(args.dir, base + '.sz.s')
+        obj_sz = os.path.join(args.dir, base + '.sz.o')
+        obj_llc = os.path.join(args.dir, base + '.llc.o')
+        shellcmd(['../llvm2ice',
+                  '-O' + args.optlevel,
+                  '--target=' + args.target,
+                  '--prefix=' + args.prefix,
+                  '-o=' + asm_sz,
+                  bitcode])
+        shellcmd([os.path.join(llvm_bin_path, 'llvm-mc'),
+                  '-arch=' + arch_map[args.target],
+                  '-x86-asm-syntax=intel',
+                  '-filetype=obj',
+                  '-o=' + obj_sz,
+                  asm_sz])
+        objs.append(obj_sz)
+        # Each original bitcode file needs to be translated by the
+        # LLVM toolchain and have its object file linked in.  There
+        # are two ways to do this: explicitly use llc, or include the
+        # .ll file in the link command.  It turns out that these two
+        # approaches can produce different semantics on some undefined
+        # bitcode behavior.  Specifically, LLVM produces different
+        # results for overflowing fptoui instructions for i32 and i64
+        # on x86-32.  As it turns out, Subzero lowering was based on
+        # inspecting the object code produced by the direct llc
+        # command, so we need to directly run llc on the bitcode, even
+        # though it makes this script longer, to avoid spurious
+        # failures.  This behavior can be inspected by switching
+        # use_llc between True and False.
+        use_llc = False
+        if use_llc:
+            shellcmd([os.path.join(llvm_bin_path, 'llc'),
+                      '-filetype=obj',
+                      '-o=' + obj_llc,
+                      bitcode])
+            objs.append(obj_llc)
+        else:
+            objs.append(bitcode)
+
+    linker = 'clang' if os.path.splitext(args.driver)[1] == '.c' else 'clang++'
+    shellcmd([os.path.join(llvm_bin_path, linker), '-g', '-m32', args.driver] +
+             objs +
+             ['-lm', '-o', os.path.join(args.dir, args.output)])