[llvm] update_test_checks: keep meta variables stable by default (PR #76748)

[Jannik Silvanus via llvm-commits]

Nicolai =?utf-8?q?Hähnle?= <nicolai.haehnle at amd.com>,
Nicolai =?utf-8?q?Hähnle?= <nicolai.haehnle at amd.com>,
Nicolai =?utf-8?q?Hähnle?= <nicolai.haehnle at amd.com>,
Nicolai =?utf-8?q?Hähnle?= <nicolai.haehnle at amd.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/76748 at github.com>


================
@@ -1241,25 +1500,136 @@ def escape_braces(match_obj):
             # Ignore any comments, since the check lines will too.
             scrubbed_line = SCRUB_IR_COMMENT_RE.sub(r"", line)
             lines[i] = scrubbed_line
-        if not preserve_names:
-            # It can happen that two matches are back-to-back and for some reason sub
-            # will not replace both of them. For now we work around this by
-            # substituting until there is no more match.
-            changed = True
-            while changed:
-                (lines[i], changed) = nameless_value_regex.subn(
-                    transform_line_vars, lines[i], count=1
-                )
-        if is_analyze:
+
+    if not preserve_names:
+        if is_asm:
+            for i, _ in enumerate(lines):
+                # It can happen that two matches are back-to-back and for some reason sub
+                # will not replace both of them. For now we work around this by
+                # substituting until there is no more match.
+                changed = True
+                while changed:
+                    (lines[i], changed) = nameless_value_regex.subn(
+                        transform_line_vars, lines[i], count=1
+                    )
+        else:
+            # LLVM IR case. Start by handling global meta variables (global IR variables,
+            # metadata, attributes)
+            for i, _ in enumerate(lines):
+                start = 0
+                while True:
+                    m = nameless_value_regex.search(lines[i][start:])
+                    if m is None:
+                        break
+                    start += m.span()[0]
+                    sub = transform_non_local_line_vars(m)
+                    if sub is not None:
+                        lines[i] = (
+                            lines[i][:start] + sub + lines[i][start + len(m.group(0)) :]
+                        )
+                    start += 1
+
+            # Collect information about new check lines and original check lines (if any)
+            new_line_infos = []
+            for line in lines:
+                filtered_line = ""
+                values = []
+                while True:
+                    m = nameless_value_regex.search(line)
+                    if m is None:
+                        filtered_line += line
+                        break
+
+                    var = get_name_from_ir_value_match(m)
+                    nameless_value = get_nameless_value_from_match(m, nameless_values)
+                    var = nameless_value.get_value_name(
+                        var, nameless_value.check_prefix
+                    )
+
+                    # Replace with a [[@@]] tag, but be sure to keep the spaces and commas.
+                    filtered_line += (
+                        line[: m.span()[0]]
+                        + m.group(1)
+                        + VARIABLE_TAG
+                        + m.group(m.lastindex)
+                    )
+                    line = line[m.span()[1] :]
+                    values.append(
+                        CheckValueInfo(
+                            nameless_value=nameless_value,
+                            var=var,
+                            prefix=nameless_value.get_ir_prefix_from_ir_value_match(m)[
+                                0
+                            ],
+                        )
+                    )
+                new_line_infos.append(CheckLineInfo(filtered_line, values))
+
+            orig_line_infos = []
+            for line in original_check_lines or []:
+                filtered_line = ""
+                values = []
+                while True:
+                    m = METAVAR_RE.search(line)
+                    if m is None:
+                        filtered_line += line
+                        break
+
+                    # Replace with a [[@@]] tag, but be sure to keep the spaces and commas.
+                    filtered_line += line[: m.span()[0]] + VARIABLE_TAG
+                    line = line[m.span()[1] :]
+                    values.append(
+                        CheckValueInfo(
+                            nameless_value=None,
+                            var=m.group(1),
+                            prefix=None,
+                        )
+                    )
+                orig_line_infos.append(CheckLineInfo(filtered_line, values))
+
+            # Compute the variable name mapping
+            committed_names = set(vars_seen)
+
+            mapping = remap_metavar_names(
+                orig_line_infos, new_line_infos, committed_names
+            )
+
+            for i, line_info in enumerate(new_line_infos):
+                line_template = line_info.line
+                line = ""
+
+                for value in line_info.values:
+                    idx = line_template.find(VARIABLE_TAG)
+                    line += line_template[:idx]
+                    line_template = line_template[idx + len(VARIABLE_TAG) :]
+
+                    key = (mapping[value.var], nameless_value.check_key)
+                    is_local_def = nameless_value.is_local_def_ir_value()
+                    if is_local_def:
+                        if mapping[value.var] in vars_seen:
+                            line += f"[[{mapping[value.var]}]]"
+                        else:
+                            line += f"[[{mapping[value.var]}:{value.prefix}{value.nameless_value.get_ir_regex()}]]"
+                            vars_seen.add(mapping[value.var])
+                    else:
+                        todo("not implemented")
----------------
jasilvanus wrote:

Maybe raise a RuntimeError?

https://github.com/llvm/llvm-project/pull/76748