[llvm] [FileCheck] Fix --enable-var-scope for numvars after reassignment (PR #157158)

[via llvm-commits]

https://github.com/Clipi-12 updated https://github.com/llvm/llvm-project/pull/157158

>From 8b826ac48b49df912fbaa76f78163a4f5d11d8b9 Mon Sep 17 00:00:00 2001
From: Clipi <clipi.dev at gmail.com>
Date: Tue, 9 Sep 2025 18:04:46 +0200
Subject: [PATCH] [FileCheck] Fix --enable-var-scope for numvars after
 reassignment

---
 llvm/lib/FileCheck/FileCheck.cpp  |  8 ++++
 llvm/test/FileCheck/var-scope.txt | 64 +++++++++++++++++++++++--------
 2 files changed, 56 insertions(+), 16 deletions(-)

diff --git a/llvm/lib/FileCheck/FileCheck.cpp b/llvm/lib/FileCheck/FileCheck.cpp
index ce35a5bad7616..9245db442611c 100644
--- a/llvm/lib/FileCheck/FileCheck.cpp
+++ b/llvm/lib/FileCheck/FileCheck.cpp
@@ -1218,6 +1218,14 @@ Pattern::MatchResult Pattern::match(StringRef Buffer,
     StringRef MatchedValue = MatchInfo[CaptureParenGroup];
     ExpressionFormat Format = DefinedNumericVariable->getImplicitFormat();
     APInt Value = Format.valueFromStringRepr(MatchedValue, SM);
+    // Numeric variables are already inserted into GlobalNumericVariableTable
+    // during parsing, but clearLocalVars might remove them, so we must
+    // reinsert them. Numeric-variable resolution does not access
+    // GlobalNumericVariableTable; it directly uses a pointer to the variable.
+    // However, other functions (such as clearLocalVars) may require active
+    // variables to be in the table.
+    Context->GlobalNumericVariableTable.try_emplace(NumericVariableDef.getKey(),
+                                                    DefinedNumericVariable);
     DefinedNumericVariable->setValue(Value, MatchedValue);
   }
 
diff --git a/llvm/test/FileCheck/var-scope.txt b/llvm/test/FileCheck/var-scope.txt
index 9b3ea0e95d143..b65eddb6d16a0 100644
--- a/llvm/test/FileCheck/var-scope.txt
+++ b/llvm/test/FileCheck/var-scope.txt
@@ -3,15 +3,15 @@
 
 ; Reference run: variables remain defined at all time when not using
 ; --enable-var-scope option.
-RUN: FileCheck --check-prefixes CHECK,LOCAL3,GLOBAL --input-file %s %s
+RUN: FileCheck --check-prefixes CHECK,CHECK-LOCAL-BOTH,CHECK-GLOBAL --input-file %s %s
 
-RUN: FileCheck --check-prefixes CHECK,GLOBAL --enable-var-scope --input-file %s %s
-RUN: %ProtectFileCheckOutput not FileCheck --check-prefixes CHECK,LOCAL1 --enable-var-scope --input-file %s %s 2>&1 \
-RUN:   | FileCheck --check-prefix ERRUNDEFLOCAL %s
-RUN: %ProtectFileCheckOutput not FileCheck --check-prefixes CHECK,LOCAL2 --enable-var-scope --input-file %s %s 2>&1 \
-RUN:   | FileCheck --check-prefix ERRUNDEFLOCNUM %s
-RUN: %ProtectFileCheckOutput not FileCheck --check-prefixes CHECK,LOCAL3 --enable-var-scope --input-file %s %s 2>&1 \
-RUN:   | FileCheck --check-prefixes ERRUNDEFLOCAL,ERRUNDEFLOCNUM %s
+RUN: FileCheck --check-prefixes CHECK,CHECK-GLOBAL --enable-var-scope --input-file %s %s
+RUN: %ProtectFileCheckOutput not FileCheck --check-prefixes CHECK,CHECK-LOCAL-TEXT --enable-var-scope --input-file %s %s 2>&1 \
+RUN:   | FileCheck --implicit-check-not "undefined variable:" --check-prefixes ERRUNDEF,ERRUNDEF-LOCAL %s
+RUN: %ProtectFileCheckOutput not FileCheck --check-prefixes CHECK,CHECK-LOCAL-NUM --enable-var-scope --input-file %s %s 2>&1 \
+RUN:   | FileCheck --implicit-check-not "undefined variable:" --check-prefixes ERRUNDEF,ERRUNDEF-LOCNUM %s
+RUN: %ProtectFileCheckOutput not FileCheck --check-prefixes CHECK,CHECK-LOCAL-BOTH --enable-var-scope --input-file %s %s 2>&1 \
+RUN:   | FileCheck --implicit-check-not "undefined variable:" --check-prefixes ERRUNDEF,ERRUNDEF-LOCAL,ERRUNDEF-LOCNUM %s
 
 local1
 global1
@@ -23,15 +23,47 @@ global2
 CHECK: [[LOCAL]][[#LOCNUM+1]]
 CHECK: [[$GLOBAL]][[#$GLOBNUM+1]]
 
-barrier:
-CHECK-LABEL: barrier
+// Barrier to clear local variables
+barrier1:
+CHECK-LABEL: barrier1
 
 local3
 global3
-LOCAL1: [[LOCAL]]3
-LOCAL2: local[[#LOCNUM+2]]
-LOCAL3: [[LOCAL]][[#LOCNUM+2]]
-GLOBAL: [[$GLOBAL]][[#$GLOBNUM+2]]
+CHECK-LOCAL-TEXT: [[LOCAL]]3
+CHECK-LOCAL-NUM: local[[#LOCNUM+2]]
+CHECK-LOCAL-BOTH: [[LOCAL]][[#LOCNUM+2]]
+CHECK-GLOBAL: [[$GLOBAL]][[#$GLOBNUM+2]]
 
-ERRUNDEFLOCAL: undefined variable: LOCAL
-ERRUNDEFLOCNUM: undefined variable: LOCNUM
+// Barrier to continue FileCheck execution even after the first fail
+barrier2:
+CHECK-LABEL: barrier2
+
+// Reassign the variables to check that clearing-after-reassigning works
+local4
+global4
+CHECK: [[LOCAL:loc[^[:digit:]]*]][[#LOCNUM:]]
+CHECK: [[$GLOBAL:glo[^[:digit:]]*]][[#$GLOBNUM:]]
+
+// Barrier to clear local variables
+barrier3:
+CHECK-LABEL: barrier3
+
+local5
+global5
+CHECK-LOCAL-TEXT: [[LOCAL]]5
+CHECK-LOCAL-NUM: local[[#LOCNUM+1]]
+CHECK-LOCAL-BOTH: [[LOCAL]][[#LOCNUM+1]]
+CHECK-GLOBAL: [[$GLOBAL]][[#$GLOBNUM+1]]
+
+
+// Check that the tests fail as expected
+ERRUNDEF-LOCAL: undefined variable: LOCAL
+ERRUNDEF-LOCNUM: undefined variable: LOCNUM
+ERRUNDEF-LOCAL: undefined variable: LOCAL
+ERRUNDEF-LOCNUM: undefined variable: LOCNUM
+
+// Look for "Input was:" to only match the error messages before the input-context.
+//
+// The regex /([[:space:]]|.)*/ matches all remaining characters,
+// to avoid fails due to --implicit-check-not
+ERRUNDEF: {{^Input was:([[:space:]]|.)*}}