[msan] Handle x86_avx512_(min|max)_p[sd]_512 intrinsics

llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp

@@ -2989,17 +2989,24 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
 
   /// Handle (SIMD arithmetic)-like intrinsics.
   ///
-  /// Instrument intrinsics with any number of arguments of the same type,
-  /// equal to the return type. The type should be simple (no aggregates or
-  /// pointers; vectors are fine).
+  /// Instrument intrinsics with any number of arguments of the same type [*],
+  /// equal to the return type, plus a specified number of trailing flags of
+  /// any type.
+  ///
+  /// [*] The type should be simple (no aggregates or pointers; vectors are
+  /// fine).
+  ///
   /// Caller guarantees that this intrinsic does not access memory.
-  bool maybeHandleSimpleNomemIntrinsic(IntrinsicInst &I) {
+  [[maybe_unused]] bool
+  maybeHandleSimpleNomemIntrinsic(IntrinsicInst &I,
+                                  unsigned int trailingFlags) {
     Type *RetTy = I.getType();
     if (!(RetTy->isIntOrIntVectorTy() || RetTy->isFPOrFPVectorTy()))
       return false;
 
     unsigned NumArgOperands = I.arg_size();
-    for (unsigned i = 0; i < NumArgOperands; ++i) {
+    assert(NumArgOperands >= trailingFlags);
+    for (unsigned i = 0; i < NumArgOperands - trailingFlags; ++i) {
       Type *Ty = I.getArgOperand(i)->getType();
       if (Ty != RetTy)
         return false;
@@ -3043,7 +3050,7 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
     }
 
     if (I.doesNotAccessMemory())
-      if (maybeHandleSimpleNomemIntrinsic(I))
+      if (maybeHandleSimpleNomemIntrinsic(I, /*trailingFlags=*/0))
         return true;
 
     // FIXME: detect and handle SSE maskstore/maskload?
@@ -4687,6 +4694,19 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
       break;
     }
 
+    // Packed
+    case Intrinsic::x86_avx512_min_ps_512:
+    case Intrinsic::x86_avx512_min_pd_512:
+    case Intrinsic::x86_avx512_max_ps_512:
+    case Intrinsic::x86_avx512_max_pd_512: {
+      // These AVX512 variants contain the rounding mode as a trailing flag.
+      // Earlier variants do not have a trailing flag and are already handled
+      // by maybeHandleSimpleNomemIntrinsic(I, 0) via handleUnknownIntrinsic.
+      bool Success = maybeHandleSimpleNomemIntrinsic(I, /*trailingFlags=*/1);
+      assert(Success);
+      break;
+    }
+
     case Intrinsic::fshl:
     case Intrinsic::fshr:
       handleFunnelShift(I);