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

* When `--enable-var-scope` is active,
`lib/FileCheck.cpp#clearLocalVars` gets called.
* That function loops through `GlobalNumericVariableTable` and then
calls `NumericVariable::clear` on most items. It also removes them from
`GlobalNumericVariableTable`.
* When reassigning an already cleared variable, `Pattern::match` calls
`NumericVariable::setValue`, but it doesn't reinsert it into
`GlobalNumericVariableTable`. Therefore, the next time `clearLocalVars`
is called, it won't be able to loop through the variables.

Fix it by reinserting them in `GlobalNumericVariableTable` inside
`Pattern::match`.

Co-authored-by: Thomas Preud'homme <thomas.preudhomme@arm.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/llvm/lib/FileCheck/FileCheck.cpp b/llvm/lib/FileCheck/FileCheck.cpp
index ce35a5b..9245db4 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);
   }