[clang] [clang][bytecode] `extOrTrunc()` when pushing builtin results (PR #204516)

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llvmorg-github-actions[bot] wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang

Author: Timm Baeder (tbaederr)

<details>
<summary>Changes</summary>

We're not necessarily using an APSInt of the appropriate size from the start, so get it to the right bitwidth here.

---
Full diff: https://github.com/llvm/llvm-project/pull/204516.diff


2 Files Affected:

- (modified) clang/lib/AST/ByteCode/InterpBuiltin.cpp (+2-2) 
- (modified) clang/test/AST/ByteCode/builtin-functions.cpp (+2) 


``````````diff
diff --git a/clang/lib/AST/ByteCode/InterpBuiltin.cpp b/clang/lib/AST/ByteCode/InterpBuiltin.cpp
index 55907bf11506b..b16a34543757b 100644
--- a/clang/lib/AST/ByteCode/InterpBuiltin.cpp
+++ b/clang/lib/AST/ByteCode/InterpBuiltin.cpp
@@ -100,7 +100,7 @@ static void pushInteger(InterpState &S, const APSInt &Val, QualType QT) {
   if (T == PT_IntAPS) {
     unsigned BitWidth = S.getASTContext().getIntWidth(QT);
     auto Result = S.allocAP<IntegralAP<true>>(BitWidth);
-    Result.copy(Val);
+    Result.copy(Val.extOrTrunc(BitWidth));
     S.Stk.push<IntegralAP<true>>(Result);
     return;
   }
@@ -108,7 +108,7 @@ static void pushInteger(InterpState &S, const APSInt &Val, QualType QT) {
   if (T == PT_IntAP) {
     unsigned BitWidth = S.getASTContext().getIntWidth(QT);
     auto Result = S.allocAP<IntegralAP<false>>(BitWidth);
-    Result.copy(Val);
+    Result.copy(Val.extOrTrunc(BitWidth));
     S.Stk.push<IntegralAP<false>>(Result);
     return;
   }
diff --git a/clang/test/AST/ByteCode/builtin-functions.cpp b/clang/test/AST/ByteCode/builtin-functions.cpp
index 57157392f6a6e..3074a84986520 100644
--- a/clang/test/AST/ByteCode/builtin-functions.cpp
+++ b/clang/test/AST/ByteCode/builtin-functions.cpp
@@ -856,6 +856,8 @@ namespace ctz {
   char ctz53[__builtin_ctzg((unsigned __int128)0x10, 42) == 4 ? 1 : -1];
   char ctz54[__builtin_ctzg((unsigned __int128)1 << (BITSIZE(__int128) - 1)) == BITSIZE(__int128) - 1 ? 1 : -1];
   char ctz55[__builtin_ctzg((unsigned __int128)1 << (BITSIZE(__int128) - 1), 42) == BITSIZE(__int128) - 1 ? 1 : -1];
+
+  static_assert(__builtin_elementwise_ctzg((__int128)42) == 1, "");
 #endif
 #ifndef __AVR__
   int ctz56 = __builtin_ctzg((unsigned _BitInt(128))0);

``````````

</details>


https://github.com/llvm/llvm-project/pull/204516