1 files changed, 95 insertions, 0 deletions

diff --git a/dynamic-layers/clang-layer/recipes-devtools/clang/files/llvm11-0008-ispc-11_0_11_1_packed_load_store_avx512.patch b/dynamic-layers/clang-layer/recipes-devtools/clang/files/llvm11-0008-ispc-11_0_11_1_packed_load_store_avx512.patch
new file mode 100644
index 00000000..9ceed0a9
--- /dev/null
+++ b/dynamic-layers/clang-layer/recipes-devtools/clang/files/llvm11-0008-ispc-11_0_11_1_packed_load_store_avx512.patch
@@ -0,0 +1,95 @@
+From c20838176e8bea9e5a176c59c78bbce9051ec987 Mon Sep 17 00:00:00 2001
+From: Naveen Saini <naveen.kumar.saini@intel.com>
+Date: Fri, 27 Aug 2021 11:41:47 +0800
+Subject: [PATCH 2/2] [X86] When storing v1i1/v2i1/v4i1 to memory, make sure we
+ store zeros in the rest of the byte
+
+We can't store garbage in the unused bits. It possible that something like zextload from i1/i2/i4 is created to read the memory. Those zextloads would be legalized assuming the extra bits are 0.
+
+I'm not sure that the code in lowerStore is executed for the v1i1/v2i1/v4i1 case. It looks like the DAG combine in combineStore may have converted them to v8i1 first. And I think we're missing some cases to avoid going to the stack in the first place. But I don't have time to investigate those things at the moment so I wanted to focus on the correctness issue.
+
+Should fix PR48147.
+
+Reviewed By: RKSimon
+
+Differential Revision: https://reviews.llvm.org/D91294
+
+Upstream-Status: Backport [https://github.com/llvm/llvm-project/commit/a4124e455e641db1e18d4221d2dacb31953fd13b]
+
+Signed-off-by: Naveen Saini <naveen.kumar.saini@intel.com>
+---
+ llvm/lib/Target/X86/X86ISelLowering.cpp | 19 ++++++++++++++-----
+ llvm/lib/Target/X86/X86InstrAVX512.td   |  3 ---
+ 2 files changed, 14 insertions(+), 8 deletions(-)
+
+diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
+index 56690c3c555b..7e673a3163b7 100644
+--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
++++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
+@@ -23549,17 +23549,22 @@ static SDValue LowerStore(SDValue Op, const X86Subtarget &Subtarget,
+   // Without AVX512DQ, we need to use a scalar type for v2i1/v4i1/v8i1 stores.
+   if (StoredVal.getValueType().isVector() &&
+       StoredVal.getValueType().getVectorElementType() == MVT::i1) {
+-    assert(StoredVal.getValueType().getVectorNumElements() <= 8 &&
+-           "Unexpected VT");
++    unsigned NumElts = StoredVal.getValueType().getVectorNumElements();
++    assert(NumElts <= 8 && "Unexpected VT");
+     assert(!St->isTruncatingStore() && "Expected non-truncating store");
+     assert(Subtarget.hasAVX512() && !Subtarget.hasDQI() &&
+            "Expected AVX512F without AVX512DQI");
+ 
++    // We must pad with zeros to ensure we store zeroes to any unused bits.
+     StoredVal = DAG.getNode(ISD::INSERT_SUBVECTOR, dl, MVT::v16i1,
+                             DAG.getUNDEF(MVT::v16i1), StoredVal,
+                             DAG.getIntPtrConstant(0, dl));
+     StoredVal = DAG.getBitcast(MVT::i16, StoredVal);
+     StoredVal = DAG.getNode(ISD::TRUNCATE, dl, MVT::i8, StoredVal);
++    // Make sure we store zeros in the extra bits.
++    if (NumElts < 8)
++      StoredVal = DAG.getZeroExtendInReg(StoredVal, dl,
++                                         MVT::getIntegerVT(NumElts));
+ 
+     return DAG.getStore(St->getChain(), dl, StoredVal, St->getBasePtr(),
+                         St->getPointerInfo(), St->getOriginalAlign(),
+@@ -44133,17 +44138,21 @@ static SDValue combineStore(SDNode *N, SelectionDAG &DAG,
+   if (VT == MVT::v1i1 && VT == StVT && Subtarget.hasAVX512() &&
+       StoredVal.getOpcode() == ISD::SCALAR_TO_VECTOR &&
+       StoredVal.getOperand(0).getValueType() == MVT::i8) {
+-    return DAG.getStore(St->getChain(), dl, StoredVal.getOperand(0),
++    SDValue Val = StoredVal.getOperand(0);
++    // We must store zeros to the unused bits.
++    Val = DAG.getZeroExtendInReg(Val, dl, MVT::i1);
++    return DAG.getStore(St->getChain(), dl, Val,
+                         St->getBasePtr(), St->getPointerInfo(),
+                         St->getOriginalAlign(),
+                         St->getMemOperand()->getFlags());
+   }
+ 
+   // Widen v2i1/v4i1 stores to v8i1.
+-  if ((VT == MVT::v2i1 || VT == MVT::v4i1) && VT == StVT &&
++  if ((VT == MVT::v1i1 || VT == MVT::v2i1 || VT == MVT::v4i1) && VT == StVT &&
+       Subtarget.hasAVX512()) {
+     unsigned NumConcats = 8 / VT.getVectorNumElements();
+-    SmallVector<SDValue, 4> Ops(NumConcats, DAG.getUNDEF(VT));
++    // We must store zeros to the unused bits.
++    SmallVector<SDValue, 4> Ops(NumConcats, DAG.getConstant(0, dl, VT));
+     Ops[0] = StoredVal;
+     StoredVal = DAG.getNode(ISD::CONCAT_VECTORS, dl, MVT::v8i1, Ops);
+     return DAG.getStore(St->getChain(), dl, StoredVal, St->getBasePtr(),
+diff --git a/llvm/lib/Target/X86/X86InstrAVX512.td b/llvm/lib/Target/X86/X86InstrAVX512.td
+index a3ad0b1c8dd6..aa1ccec02f2a 100644
+--- a/llvm/lib/Target/X86/X86InstrAVX512.td
++++ b/llvm/lib/Target/X86/X86InstrAVX512.td
+@@ -2871,9 +2871,6 @@ def : Pat<(i64 (bitconvert (v64i1 VK64:$src))),
+ 
+ // Load/store kreg
+ let Predicates = [HasDQI] in {
+-  def : Pat<(store VK1:$src, addr:$dst),
+-            (KMOVBmk addr:$dst, (COPY_TO_REGCLASS VK1:$src, VK8))>;
+-
+   def : Pat<(v1i1 (load addr:$src)),
+             (COPY_TO_REGCLASS (KMOVBkm addr:$src), VK1)>;
+   def : Pat<(v2i1 (load addr:$src)),
+-- 
+2.17.1
+