1 files changed, 26 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/AArch64/MCTargetDesc/AArch64AddressingModes.h b/contrib/llvm/lib/Target/AArch64/MCTargetDesc/AArch64AddressingModes.h
index ed24343..648b1df 100644
--- a/contrib/llvm/lib/Target/AArch64/MCTargetDesc/AArch64AddressingModes.h
+++ b/contrib/llvm/lib/Target/AArch64/MCTargetDesc/AArch64AddressingModes.h
@@ -364,6 +364,32 @@ static inline float getFPImmFloat(unsigned Imm) {
   return FPUnion.F;
 }
 
+/// getFP16Imm - Return an 8-bit floating-point version of the 16-bit
+/// floating-point value. If the value cannot be represented as an 8-bit
+/// floating-point value, then return -1.
+static inline int getFP16Imm(const APInt &Imm) {
+  uint32_t Sign = Imm.lshr(15).getZExtValue() & 1;
+  int32_t Exp = (Imm.lshr(10).getSExtValue() & 0x1f) - 15;  // -14 to 15
+  int32_t Mantissa = Imm.getZExtValue() & 0x3ff;  // 10 bits
+
+  // We can handle 4 bits of mantissa.
+  // mantissa = (16+UInt(e:f:g:h))/16.
+  if (Mantissa & 0x3f)
+    return -1;
+  Mantissa >>= 6;
+
+  // We can handle 3 bits of exponent: exp == UInt(NOT(b):c:d)-3
+  if (Exp < -3 || Exp > 4)
+    return -1;
+  Exp = ((Exp+3) & 0x7) ^ 4;
+
+  return ((int)Sign << 7) | (Exp << 4) | Mantissa;
+}
+
+static inline int getFP16Imm(const APFloat &FPImm) {
+  return getFP16Imm(FPImm.bitcastToAPInt());
+}
+
 /// getFP32Imm - Return an 8-bit floating-point version of the 32-bit
 /// floating-point value. If the value cannot be represented as an 8-bit
 /// floating-point value, then return -1.