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-rw-r--r--llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp74
1 files changed, 74 insertions, 0 deletions
diff --git a/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp b/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp
index ef3318ba758..9777c0d85e9 100644
--- a/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp
+++ b/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp
@@ -431,4 +431,78 @@ void DecodeScalarMoveMask(MVT VT, bool IsLoad, SmallVectorImpl<int> &Mask) {
for (unsigned i = 1; i < NumElts; i++)
Mask.push_back(IsLoad ? static_cast<int>(SM_SentinelZero) : i);
}
+
+void DecodeEXTRQIMask(int Len, int Idx,
+ SmallVectorImpl<int> &ShuffleMask) {
+ // Only the bottom 6 bits are valid for each immediate.
+ Len &= 0x3F;
+ Idx &= 0x3F;
+
+ // We can only decode this bit extraction instruction as a shuffle if both the
+ // length and index work with whole bytes.
+ if (0 != (Len % 8) || 0 != (Idx % 8))
+ return;
+
+ // A length of zero is equivalent to a bit length of 64.
+ if (Len == 0)
+ Len = 64;
+
+ // If the length + index exceeds the bottom 64 bits the result is undefined.
+ if ((Len + Idx) > 64) {
+ ShuffleMask.append(16, SM_SentinelUndef);
+ return;
+ }
+
+ // Convert index and index to work with bytes.
+ Len /= 8;
+ Idx /= 8;
+
+ // EXTRQ: Extract Len bytes starting from Idx. Zero pad the remaining bytes
+ // of the lower 64-bits. The upper 64-bits are undefined.
+ for (int i = 0; i != Len; ++i)
+ ShuffleMask.push_back(i + Idx);
+ for (int i = Len; i != 8; ++i)
+ ShuffleMask.push_back(SM_SentinelZero);
+ for (int i = 8; i != 16; ++i)
+ ShuffleMask.push_back(SM_SentinelUndef);
+}
+
+void DecodeINSERTQIMask(int Len, int Idx,
+ SmallVectorImpl<int> &ShuffleMask) {
+ // Only the bottom 6 bits are valid for each immediate.
+ Len &= 0x3F;
+ Idx &= 0x3F;
+
+ // We can only decode this bit insertion instruction as a shuffle if both the
+ // length and index work with whole bytes.
+ if (0 != (Len % 8) || 0 != (Idx % 8))
+ return;
+
+ // A length of zero is equivalent to a bit length of 64.
+ if (Len == 0)
+ Len = 64;
+
+ // If the length + index exceeds the bottom 64 bits the result is undefined.
+ if ((Len + Idx) > 64) {
+ ShuffleMask.append(16, SM_SentinelUndef);
+ return;
+ }
+
+ // Convert index and index to work with bytes.
+ Len /= 8;
+ Idx /= 8;
+
+ // INSERTQ: Extract lowest Len bytes from lower half of second source and
+ // insert over first source starting at Idx byte. The upper 64-bits are
+ // undefined.
+ for (int i = 0; i != Idx; ++i)
+ ShuffleMask.push_back(i);
+ for (int i = 0; i != Len; ++i)
+ ShuffleMask.push_back(i + 16);
+ for (int i = Idx + Len; i != 8; ++i)
+ ShuffleMask.push_back(i);
+ for (int i = 8; i != 16; ++i)
+ ShuffleMask.push_back(SM_SentinelUndef);
+}
+
} // llvm namespace
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