[msan] Handle X86 SIMD bitshift intrinsics.

llvm-svn: 202712

1 files changed, 119 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
index 27fd9d4d49d..95129d2df17 100644
--- a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
@@ -1827,6 +1827,48 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
     }
   }
 
+  // Given a scalar or vector, extract lower 64 bits (or less), and return all
+  // zeroes if it is zero, and all ones otherwise.
+  Value *Lower64ShadowExtend(IRBuilder<> &IRB, Value *S, Type *T) {
+    if (S->getType()->isVectorTy())
+      S = CreateShadowCast(IRB, S, IRB.getInt64Ty(), /* Signed */ true);
+    assert(S->getType()->getPrimitiveSizeInBits() <= 64);
+    Value *S2 = IRB.CreateICmpNE(S, getCleanShadow(S));
+    return CreateShadowCast(IRB, S2, T, /* Signed */ true);
+  }
+
+  Value *VariableShadowExtend(IRBuilder<> &IRB, Value *S) {
+    Type *T = S->getType();
+    assert(T->isVectorTy());
+    Value *S2 = IRB.CreateICmpNE(S, getCleanShadow(S));
+    return IRB.CreateSExt(S2, T);
+  }
+
+  // \brief Instrument vector shift instrinsic.
+  //
+  // This function instruments intrinsics like int_x86_avx2_psll_w.
+  // Intrinsic shifts %In by %ShiftSize bits.
+  // %ShiftSize may be a vector. In that case the lower 64 bits determine shift
+  // size, and the rest is ignored. Behavior is defined even if shift size is
+  // greater than register (or field) width.
+  void handleVectorShiftIntrinsic(IntrinsicInst &I, bool Variable) {
+    assert(I.getNumArgOperands() == 2);
+    IRBuilder<> IRB(&I);
+    // If any of the S2 bits are poisoned, the whole thing is poisoned.
+    // Otherwise perform the same shift on S1.
+    Value *S1 = getShadow(&I, 0);
+    Value *S2 = getShadow(&I, 1);
+    Value *S2Conv = Variable ? VariableShadowExtend(IRB, S2)
+                             : Lower64ShadowExtend(IRB, S2, getShadowTy(&I));
+    Value *V1 = I.getOperand(0);
+    Value *V2 = I.getOperand(1);
+    Value *Shift = IRB.CreateCall2(I.getCalledValue(),
+                                   IRB.CreateBitCast(S1, V1->getType()), V2);
+    Shift = IRB.CreateBitCast(Shift, getShadowTy(&I));
+    setShadow(&I, IRB.CreateOr(Shift, S2Conv));
+    setOriginForNaryOp(I);
+  }
+
   void visitIntrinsicInst(IntrinsicInst &I) {
     switch (I.getIntrinsicID()) {
     case llvm::Intrinsic::bswap:
@@ -1866,6 +1908,83 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
     case llvm::Intrinsic::x86_sse_cvttps2pi:
       handleVectorConvertIntrinsic(I, 2);
       break;
+    case llvm::Intrinsic::x86_avx512_psll_dq:
+    case llvm::Intrinsic::x86_avx512_psrl_dq:
+    case llvm::Intrinsic::x86_avx2_psll_w:
+    case llvm::Intrinsic::x86_avx2_psll_d:
+    case llvm::Intrinsic::x86_avx2_psll_q:
+    case llvm::Intrinsic::x86_avx2_pslli_w:
+    case llvm::Intrinsic::x86_avx2_pslli_d:
+    case llvm::Intrinsic::x86_avx2_pslli_q:
+    case llvm::Intrinsic::x86_avx2_psll_dq:
+    case llvm::Intrinsic::x86_avx2_psrl_w:
+    case llvm::Intrinsic::x86_avx2_psrl_d:
+    case llvm::Intrinsic::x86_avx2_psrl_q:
+    case llvm::Intrinsic::x86_avx2_psra_w:
+    case llvm::Intrinsic::x86_avx2_psra_d:
+    case llvm::Intrinsic::x86_avx2_psrli_w:
+    case llvm::Intrinsic::x86_avx2_psrli_d:
+    case llvm::Intrinsic::x86_avx2_psrli_q:
+    case llvm::Intrinsic::x86_avx2_psrai_w:
+    case llvm::Intrinsic::x86_avx2_psrai_d:
+    case llvm::Intrinsic::x86_avx2_psrl_dq:
+    case llvm::Intrinsic::x86_sse2_psll_w:
+    case llvm::Intrinsic::x86_sse2_psll_d:
+    case llvm::Intrinsic::x86_sse2_psll_q:
+    case llvm::Intrinsic::x86_sse2_pslli_w:
+    case llvm::Intrinsic::x86_sse2_pslli_d:
+    case llvm::Intrinsic::x86_sse2_pslli_q:
+    case llvm::Intrinsic::x86_sse2_psll_dq:
+    case llvm::Intrinsic::x86_sse2_psrl_w:
+    case llvm::Intrinsic::x86_sse2_psrl_d:
+    case llvm::Intrinsic::x86_sse2_psrl_q:
+    case llvm::Intrinsic::x86_sse2_psra_w:
+    case llvm::Intrinsic::x86_sse2_psra_d:
+    case llvm::Intrinsic::x86_sse2_psrli_w:
+    case llvm::Intrinsic::x86_sse2_psrli_d:
+    case llvm::Intrinsic::x86_sse2_psrli_q:
+    case llvm::Intrinsic::x86_sse2_psrai_w:
+    case llvm::Intrinsic::x86_sse2_psrai_d:
+    case llvm::Intrinsic::x86_sse2_psrl_dq:
+    case llvm::Intrinsic::x86_mmx_psll_w:
+    case llvm::Intrinsic::x86_mmx_psll_d:
+    case llvm::Intrinsic::x86_mmx_psll_q:
+    case llvm::Intrinsic::x86_mmx_pslli_w:
+    case llvm::Intrinsic::x86_mmx_pslli_d:
+    case llvm::Intrinsic::x86_mmx_pslli_q:
+    case llvm::Intrinsic::x86_mmx_psrl_w:
+    case llvm::Intrinsic::x86_mmx_psrl_d:
+    case llvm::Intrinsic::x86_mmx_psrl_q:
+    case llvm::Intrinsic::x86_mmx_psra_w:
+    case llvm::Intrinsic::x86_mmx_psra_d:
+    case llvm::Intrinsic::x86_mmx_psrli_w:
+    case llvm::Intrinsic::x86_mmx_psrli_d:
+    case llvm::Intrinsic::x86_mmx_psrli_q:
+    case llvm::Intrinsic::x86_mmx_psrai_w:
+    case llvm::Intrinsic::x86_mmx_psrai_d:
+      handleVectorShiftIntrinsic(I, /* Variable */ false);
+      break;
+    case llvm::Intrinsic::x86_avx2_psllv_d:
+    case llvm::Intrinsic::x86_avx2_psllv_d_256:
+    case llvm::Intrinsic::x86_avx2_psllv_q:
+    case llvm::Intrinsic::x86_avx2_psllv_q_256:
+    case llvm::Intrinsic::x86_avx2_psrlv_d:
+    case llvm::Intrinsic::x86_avx2_psrlv_d_256:
+    case llvm::Intrinsic::x86_avx2_psrlv_q:
+    case llvm::Intrinsic::x86_avx2_psrlv_q_256:
+    case llvm::Intrinsic::x86_avx2_psrav_d:
+    case llvm::Intrinsic::x86_avx2_psrav_d_256:
+      handleVectorShiftIntrinsic(I, /* Variable */ true);
+      break;
+
+    // Byte shifts are not implemented.
+    // case llvm::Intrinsic::x86_avx512_psll_dq_bs:
+    // case llvm::Intrinsic::x86_avx512_psrl_dq_bs:
+    // case llvm::Intrinsic::x86_avx2_psll_dq_bs:
+    // case llvm::Intrinsic::x86_avx2_psrl_dq_bs:
+    // case llvm::Intrinsic::x86_sse2_psll_dq_bs:
+    // case llvm::Intrinsic::x86_sse2_psrl_dq_bs:
+
     default:
       if (!handleUnknownIntrinsic(I))
         visitInstruction(I);