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-rw-r--r--contrib/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.cpp68
1 files changed, 67 insertions, 1 deletions
diff --git a/contrib/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.cpp b/contrib/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.cpp
index bedccb5..2a97cd6 100644
--- a/contrib/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.cpp
+++ b/contrib/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.cpp
@@ -972,7 +972,7 @@ bool A64Imms::isLogicalImm(unsigned RegWidth, uint64_t Imm, uint32_t &Bits) {
// Now we have to work out the amount of rotation needed. The first part of
// this calculation is actually independent of RepeatWidth, but the complex
// case will depend on it.
- Rotation = CountTrailingZeros_64(Imm);
+ Rotation = countTrailingZeros(Imm);
if (Rotation == 0) {
// There were no leading zeros, which means it's either in place or there
// are 1s at each end (e.g. 0x8003 needs rotating).
@@ -1105,3 +1105,69 @@ bool A64Imms::isOnlyMOVNImm(int RegWidth, uint64_t Value,
return isMOVNImm(RegWidth, Value, UImm16, Shift);
}
+
+// decodeNeonModShiftImm - Decode a Neon OpCmode value into the
+// the shift amount and the shift type (shift zeros or ones in) and
+// returns whether the OpCmode value implies a shift operation.
+bool A64Imms::decodeNeonModShiftImm(unsigned OpCmode, unsigned &ShiftImm,
+ unsigned &ShiftOnesIn) {
+ ShiftImm = 0;
+ ShiftOnesIn = false;
+ bool HasShift = true;
+
+ if (OpCmode == 0xe) {
+ // movi byte
+ HasShift = false;
+ } else if (OpCmode == 0x1e) {
+ // movi 64-bit bytemask
+ HasShift = false;
+ } else if ((OpCmode & 0xc) == 0x8) {
+ // shift zeros, per halfword
+ ShiftImm = ((OpCmode & 0x2) >> 1);
+ } else if ((OpCmode & 0x8) == 0) {
+ // shift zeros, per word
+ ShiftImm = ((OpCmode & 0x6) >> 1);
+ } else if ((OpCmode & 0xe) == 0xc) {
+ // shift ones, per word
+ ShiftOnesIn = true;
+ ShiftImm = (OpCmode & 0x1);
+ } else {
+ // per byte, per bytemask
+ llvm_unreachable("Unsupported Neon modified immediate");
+ }
+
+ return HasShift;
+}
+
+// decodeNeonModImm - Decode a NEON modified immediate and OpCmode values
+// into the element value and the element size in bits.
+uint64_t A64Imms::decodeNeonModImm(unsigned Val, unsigned OpCmode,
+ unsigned &EltBits) {
+ uint64_t DecodedVal = Val;
+ EltBits = 0;
+
+ if (OpCmode == 0xe) {
+ // movi byte
+ EltBits = 8;
+ } else if (OpCmode == 0x1e) {
+ // movi 64-bit bytemask
+ DecodedVal = 0;
+ for (unsigned ByteNum = 0; ByteNum < 8; ++ByteNum) {
+ if ((Val >> ByteNum) & 1)
+ DecodedVal |= (uint64_t)0xff << (8 * ByteNum);
+ }
+ EltBits = 64;
+ } else if ((OpCmode & 0xc) == 0x8) {
+ // shift zeros, per halfword
+ EltBits = 16;
+ } else if ((OpCmode & 0x8) == 0) {
+ // shift zeros, per word
+ EltBits = 32;
+ } else if ((OpCmode & 0xe) == 0xc) {
+ // shift ones, per word
+ EltBits = 32;
+ } else {
+ llvm_unreachable("Unsupported Neon modified immediate");
+ }
+ return DecodedVal;
+}
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