Adapt to Clang 12 trunk Expr::getIntegerConstantExpression

<https://github.com/llvm/llvm-project/commit/
36036aa70ec1df7b51b5d30b2dd8090ad2b6e783> "Reapply 'Rename/refactor
isIntegerConstantExpression to getIntegerConstantExpression'"

Change-Id: I99277601fe7ffa3e0e5d22a4b3aaca4f51551ab3
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/99570
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

4 files changed, 60 insertions, 40 deletions

diff --git a/compilerplugins/clang/compat.hxx b/compilerplugins/clang/compat.hxx
index 76f076621394..8a1a728bd95b 100644
--- a/compilerplugins/clang/compat.hxx
+++ b/compilerplugins/clang/compat.hxx
@@ -174,6 +174,17 @@ inline bool EvaluateAsInt(clang::Expr const * expr, llvm::APSInt& intRes, const
 #endif
 }
 
+inline llvm::Optional<llvm::APSInt> getIntegerConstantExpr(
+    clang::Expr const * expr, clang::ASTContext const & context)
+{
+#if CLANG_VERSION >= 120000
+    return expr->getIntegerConstantExpr(context);
+#else
+    llvm::APSInt res;
+    return expr->isIntegerConstantExpr(res, context) ? res : llvm::Optional<llvm::APSInt>();
+#endif
+}
+
 inline clang::Expr * getSubExpr(clang::MaterializeTemporaryExpr const * expr) {
 #if CLANG_VERSION >= 100000
     return expr->getSubExpr();
diff --git a/compilerplugins/clang/empty.cxx b/compilerplugins/clang/empty.cxx
index 0eaa4e287852..c3cc86520f47 100644
--- a/compilerplugins/clang/empty.cxx
+++ b/compilerplugins/clang/empty.cxx
@@ -12,6 +12,7 @@
 #include <cassert>
 
 #include "check.hxx"
+#include "compat.hxx"
 #include "plugin.hxx"
 
 // Warn about checks whether a container is empty done via an (expensive) call to obtain the
@@ -72,15 +73,19 @@ private:
         {
             return;
         }
-        APSInt val;
-        if (rhs->isValueDependent() || !rhs->isIntegerConstantExpr(val, compiler.getASTContext()))
+        if (rhs->isValueDependent())
+        {
+            return;
+        }
+        auto const val = compat::getIntegerConstantExpr(rhs, compiler.getASTContext());
+        if (!val)
         {
             return;
         }
         switch (op)
         {
             case BO_LT:
-                if (val.getExtValue() == 1)
+                if (val->getExtValue() == 1)
                 {
                     report(DiagnosticsEngine::Warning,
                            "replace a comparison like 'strlen(e) < 1' with 'e[0] == '\\0''",
@@ -89,7 +94,7 @@ private:
                 }
                 break;
             case BO_GT:
-                if (val.getExtValue() == 0)
+                if (val->getExtValue() == 0)
                 {
                     report(DiagnosticsEngine::Warning,
                            "replace a comparison like 'strlen(e) > 0' with 'e[0] != '\\0''",
@@ -98,7 +103,7 @@ private:
                 }
                 break;
             case BO_LE:
-                if (val.getExtValue() == 0)
+                if (val->getExtValue() == 0)
                 {
                     report(DiagnosticsEngine::Warning,
                            "replace a comparison like 'strlen(e) <= 0' with 'e[0] == '\\0''",
@@ -107,7 +112,7 @@ private:
                 }
                 break;
             case BO_GE:
-                if (val.getExtValue() == 1)
+                if (val->getExtValue() == 1)
                 {
                     report(DiagnosticsEngine::Warning,
                            "replace a comparison like 'strlen(e) >= 1' with 'e[0] != '\\0''",
@@ -116,7 +121,7 @@ private:
                 }
                 break;
             case BO_EQ:
-                if (val.getExtValue() == 0)
+                if (val->getExtValue() == 0)
                 {
                     report(DiagnosticsEngine::Warning,
                            "replace a comparison like 'strlen(e) == 0' with 'e[0] == '\\0''",
@@ -125,7 +130,7 @@ private:
                 }
                 break;
             case BO_NE:
-                if (val.getExtValue() == 0)
+                if (val->getExtValue() == 0)
                 {
                     report(DiagnosticsEngine::Warning,
                            "replace a comparison like 'strlen(e) != 0' with 'e[0] != '\\0''",
diff --git a/compilerplugins/clang/literaltoboolconversion.cxx b/compilerplugins/clang/literaltoboolconversion.cxx
index 6bfef41b6cc0..c3f4c7a62e60 100644
--- a/compilerplugins/clang/literaltoboolconversion.cxx
+++ b/compilerplugins/clang/literaltoboolconversion.cxx
@@ -125,23 +125,25 @@ void LiteralToBoolConversion::handleImplicitCastSubExpr(
         handleImplicitCastSubExpr(castExpr, op->getFalseExpr());
         return;
     }
-    APSInt res;
-    if (!subExpr->isValueDependent()
-        && subExpr->isIntegerConstantExpr(res, compiler.getASTContext())
-        && res.getLimitedValue() <= 1)
-    {
-        SourceLocation loc { compat::getBeginLoc(subExpr) };
-        while (compiler.getSourceManager().isMacroArgExpansion(loc)) {
-            loc = compiler.getSourceManager().getImmediateMacroCallerLoc(loc);
-        }
-        if (compiler.getSourceManager().isMacroBodyExpansion(loc)) {
-            StringRef name { Lexer::getImmediateMacroName(
-                loc, compiler.getSourceManager(), compiler.getLangOpts()) };
-            if (name == "sal_False" || name == "sal_True") {
-                loc = compat::getImmediateExpansionRange(compiler.getSourceManager(), loc).first;
-            }
-            if (isSharedCAndCppCode(loc)) {
-                return;
+    if (!subExpr->isValueDependent()) {
+        if (auto const res = compat::getIntegerConstantExpr(subExpr, compiler.getASTContext())) {
+            if (res->getLimitedValue() <= 1)
+            {
+                SourceLocation loc { compat::getBeginLoc(subExpr) };
+                while (compiler.getSourceManager().isMacroArgExpansion(loc)) {
+                    loc = compiler.getSourceManager().getImmediateMacroCallerLoc(loc);
+                }
+                if (compiler.getSourceManager().isMacroBodyExpansion(loc)) {
+                    StringRef name { Lexer::getImmediateMacroName(
+                            loc, compiler.getSourceManager(), compiler.getLangOpts()) };
+                    if (name == "sal_False" || name == "sal_True") {
+                        loc = compat::getImmediateExpansionRange(compiler.getSourceManager(), loc)
+                            .first;
+                    }
+                    if (isSharedCAndCppCode(loc)) {
+                        return;
+                    }
+                }
             }
         }
     }
@@ -209,17 +211,17 @@ void LiteralToBoolConversion::handleImplicitCastSubExpr(
             compat::getBeginLoc(expr2))
             << castExpr->getCastKindName() << subExpr->getType()
             << castExpr->getType() << expr2->getSourceRange();
-    } else if (!subExpr->isValueDependent()
-               && subExpr->isIntegerConstantExpr(res, compiler.getASTContext()))
-    {
-        report(
-            DiagnosticsEngine::Warning,
-            ("implicit conversion (%0) of integer constant expression of type"
-             " %1 with value %2 to %3"),
-            compat::getBeginLoc(expr2))
-            << castExpr->getCastKindName() << subExpr->getType()
-            << res.toString(10) << castExpr->getType()
-            << expr2->getSourceRange();
+    } else if (!subExpr->isValueDependent()) {
+        if (auto const res = compat::getIntegerConstantExpr(subExpr, compiler.getASTContext())) {
+            report(
+                DiagnosticsEngine::Warning,
+                ("implicit conversion (%0) of integer constant expression of type"
+                 " %1 with value %2 to %3"),
+                compat::getBeginLoc(expr2))
+                << castExpr->getCastKindName() << subExpr->getType()
+                << res->toString(10) << castExpr->getType()
+                << expr2->getSourceRange();
+        }
     }
 }
 
diff --git a/compilerplugins/clang/unsignedcompare.cxx b/compilerplugins/clang/unsignedcompare.cxx
index d9b8f144ca77..7337f45223d4 100644
--- a/compilerplugins/clang/unsignedcompare.cxx
+++ b/compilerplugins/clang/unsignedcompare.cxx
@@ -199,12 +199,14 @@ private:
             return nullptr;
         }
         // Filter out e.g. `size_t(-1)`:
-        APSInt val;
-        if (!e2->isValueDependent() && e2->isIntegerConstantExpr(val, compiler.getASTContext()))
+        if (!e2->isValueDependent())
         {
-            if (val.isNegative())
+            if (auto const val = compat::getIntegerConstantExpr(e2, compiler.getASTContext()))
             {
-                return nullptr;
+                if (val->isNegative())
+                {
+                    return nullptr;
+                }
             }
         }
         auto loc = compat::getBeginLoc(e);