[llvm] eae84b4 - [MSAN] Handle x86 {round,min,max}sd intrinsics

[Gui Andrade via llvm-commits]

Author: Gui Andrade
Date: 2020-06-27T06:46:04Z
New Revision: eae84b41fe8e138bf0425ff4d009dee81574620a

URL: https://github.com/llvm/llvm-project/commit/eae84b41fe8e138bf0425ff4d009dee81574620a
DIFF: https://github.com/llvm/llvm-project/commit/eae84b41fe8e138bf0425ff4d009dee81574620a.diff

LOG: [MSAN] Handle x86 {round,min,max}sd intrinsics

These need special handling over the simple vector intrinsics as they
behave more like a shuffle operation: taking the top half of the vector
from one input, and the bottom half separately. Previously, these were
being handled as though all bits of all operands were combined.

Differential Revision: https://reviews.llvm.org/D82398

Added: 
    

Modified: 
    llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
index b30ef4323b77..d8df5ad857cc 100644
--- a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
@@ -3046,6 +3046,32 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
     SOC.Done(&I);
   }
 
+  // Instrument _mm_*_sd intrinsics
+  void handleUnarySdIntrinsic(IntrinsicInst &I) {
+    IRBuilder<> IRB(&I);
+    Value *First = getShadow(&I, 0);
+    Value *Second = getShadow(&I, 1);
+    // High word of first operand, low word of second
+    Value *Shadow =
+        IRB.CreateShuffleVector(First, Second, llvm::makeArrayRef<int>({2, 1}));
+
+    setShadow(&I, Shadow);
+    setOriginForNaryOp(I);
+  }
+
+  void handleBinarySdIntrinsic(IntrinsicInst &I) {
+    IRBuilder<> IRB(&I);
+    Value *First = getShadow(&I, 0);
+    Value *Second = getShadow(&I, 1);
+    Value *OrShadow = IRB.CreateOr(First, Second);
+    // High word of first operand, low word of both OR'd together
+    Value *Shadow = IRB.CreateShuffleVector(First, OrShadow,
+                                            llvm::makeArrayRef<int>({2, 1}));
+
+    setShadow(&I, Shadow);
+    setOriginForNaryOp(I);
+  }
+
   void visitIntrinsicInst(IntrinsicInst &I) {
     switch (I.getIntrinsicID()) {
     case Intrinsic::lifetime_start:
@@ -3285,6 +3311,14 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
       handlePclmulIntrinsic(I);
       break;
 
+    case Intrinsic::x86_sse41_round_sd:
+      handleUnarySdIntrinsic(I);
+      break;
+    case Intrinsic::x86_sse2_max_sd:
+    case Intrinsic::x86_sse2_min_sd:
+      handleBinarySdIntrinsic(I);
+      break;
+
     case Intrinsic::is_constant:
       // The result of llvm.is.constant() is always defined.
       setShadow(&I, getCleanShadow(&I));