[AMDGPU][test] fix the error case in update_mc_test_check script (#112731)

update_mc_test_check script handle the "error case testline" wrong in
three cases:

1. when user select "--llvm-mc-binary" with a path, the script does not
add "not" on top of the "--llvm-mc-binary" and thus getting non-zero
exit code and failed.
2. When "not" is presented in runline while not all testlines are
expected to fail, the script need to check if the "not" is needed when
it execute llvm-mc line by line. Otherwise the script will fail on
testline which is passing.
3. When there are multiple runlines, the error checkline need to use
correct line offset for "[[LINE-X]]"

This patch solve these three issues

Author: broxigarchen

llvm/test/tools/UpdateTestChecks/update_mc_test_checks/Inputs/amdgpu_asm_err.s

@@ -1,3 +1,6 @@
-// RUN: not llvm-mc -triple=amdgcn -show-encoding %s 2>&1 | FileCheck --check-prefixes=CHECK %s
+// RUN: not llvm-mc -triple=amdgcn -show-encoding %s 2>&1 | FileCheck --check-prefixes=CHECKA %s
+// RUN: not llvm-mc -triple=amdgcn %s 2>&1 | FileCheck --check-prefixes=CHECKB %s
 
 v_bfrev_b32 v5, v299
+
+v_bfrev_b32 v5, v1

llvm/test/tools/UpdateTestChecks/update_mc_test_checks/Inputs/amdgpu_asm_err.s.expected

@@ -1,5 +1,11 @@
 // NOTE: Assertions have been autogenerated by utils/update_mc_test_checks.py
-// RUN: not llvm-mc -triple=amdgcn -show-encoding %s 2>&1 | FileCheck --check-prefixes=CHECK %s
+// RUN: not llvm-mc -triple=amdgcn -show-encoding %s 2>&1 | FileCheck --check-prefixes=CHECKA %s
+// RUN: not llvm-mc -triple=amdgcn %s 2>&1 | FileCheck --check-prefixes=CHECKB %s
 
 v_bfrev_b32 v5, v299
-// CHECK: :[[@LINE-1]]:17: error: register index is out of range
+// CHECKA: :[[@LINE-1]]:17: error: register index is out of range
+// CHECKB: :[[@LINE-2]]:17: error: register index is out of range
+
+v_bfrev_b32 v5, v1
+// CHECKA: v_bfrev_b32_e32 v5, v1                  ; encoding: [0x01,0x71,0x0a,0x7e]
+// CHECKB: v_bfrev_b32_e32 v5, v1

llvm/utils/UpdateTestChecks/common.py

@@ -2470,6 +2470,7 @@ def get_autogennote_suffix(parser, args):
             "verbose",
             "force_update",
             "reset_variable_names",
+            "llvm_mc_binary",
         ):
             continue
         value = getattr(args, action.dest)

llvm/utils/update_mc_test_checks.py

@@ -16,15 +16,14 @@
 
 mc_LIKE_TOOLS = [
     "llvm-mc",
-    "not llvm-mc",
 ]
 ERROR_RE = re.compile(r":\d+: (warning|error): .*")
 ERROR_CHECK_RE = re.compile(r"# COM: .*")
 OUTPUT_SKIPPED_RE = re.compile(r"(.text)")
 COMMENT = {"asm": "//", "dasm": "#"}
 
 
-def invoke_tool(exe, cmd_args, testline, verbose=False):
+def invoke_tool(exe, check_rc, cmd_args, testline, verbose=False):
     if isinstance(cmd_args, list):
         args = [applySubstitutions(a, substitutions) for a in cmd_args]
     else:
@@ -33,7 +32,15 @@ def invoke_tool(exe, cmd_args, testline, verbose=False):
     cmd = 'echo "' + testline + '" | ' + exe + " " + args
     if verbose:
         print("Command: ", cmd)
-    out = subprocess.check_output(cmd, shell=True)
+
+    out = subprocess.run(
+        cmd,
+        shell=True,
+        check=check_rc,
+        stdout=subprocess.PIPE,
+        stderr=subprocess.DEVNULL,
+    ).stdout
+
     # Fix line endings to unix CR style.
     return out.decode().replace("\r\n", "\n")
 
@@ -102,8 +109,16 @@ def getStdCheckLine(prefix, output, mc_mode):
     return o
 
 
-def getErrCheckLine(prefix, output, mc_mode):
-    return COMMENT[mc_mode] + " " + prefix + ": " + ":[[@LINE-1]]" + output + "\n"
+def getErrCheckLine(prefix, output, mc_mode, line_offset=1):
+    return (
+        COMMENT[mc_mode]
+        + " "
+        + prefix
+        + ": "
+        + ":[[@LINE-{}]]".format(line_offset)
+        + output
+        + "\n"
+    )
 
 
 def main():
@@ -174,11 +189,19 @@ def main():
             assert len(commands) >= 2
             mc_cmd = " | ".join(commands[:-1])
             filecheck_cmd = commands[-1]
-            mc_tool = mc_cmd.split(" ")[0]
 
             # special handling for negating exit status
-            if mc_tool == "not":
-                mc_tool = mc_tool + " " + mc_cmd.split(" ")[1]
+            # if not is used in runline, disable rc check, since
+            # the command might or might not
+            # return non-zero code on a single line run
+            check_rc = True
+            mc_cmd_args = mc_cmd.strip().split()
+            if mc_cmd_args[0] == "not":
+                check_rc = False
+                mc_tool = mc_cmd_args[1]
+                mc_cmd = mc_cmd[len(mc_cmd_args[0]) :].strip()
+            else:
+                mc_tool = mc_cmd_args[0]
 
             triple_in_cmd = None
             m = common.TRIPLE_ARG_RE.search(mc_cmd)
@@ -211,6 +234,7 @@ def main():
                 (
                     check_prefixes,
                     mc_tool,
+                    check_rc,
                     mc_cmd_args,
                     triple_in_cmd,
                     march_in_cmd,
@@ -231,6 +255,7 @@ def main():
         for (
             prefixes,
             mc_tool,
+            check_rc,
             mc_args,
             triple_in_cmd,
             march_in_cmd,
@@ -249,6 +274,7 @@ def main():
                 # get output for each testline
                 out = invoke_tool(
                     ti.args.llvm_mc_binary or mc_tool,
+                    check_rc,
                     mc_args,
                     line,
                     verbose=ti.args.verbose,
@@ -305,6 +331,9 @@ def main():
             # each run_id can only be used once
             gen_prefix = ""
             used_runid = set()
+
+            # line number diff between generated prefix and testline
+            line_offset = 1
             for prefix, tup in p_dict_sorted.items():
                 o, run_ids = tup
 
@@ -321,9 +350,13 @@ def main():
                     used_prefixes.add(prefix)
 
                     if hasErr(o):
-                        gen_prefix += getErrCheckLine(prefix, o, mc_mode)
+                        newline = getErrCheckLine(prefix, o, mc_mode, line_offset)
                     else:
-                        gen_prefix += getStdCheckLine(prefix, o, mc_mode)
+                        newline = getStdCheckLine(prefix, o, mc_mode)
+
+                    if newline:
+                        gen_prefix += newline
+                        line_offset += 1
 
             generated_prefixes[input_line] = gen_prefix.rstrip("\n")