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authorTSR Berry <20988865+TSRBerry@users.noreply.github.com>2023-04-08 01:22:00 +0200
committerMary <thog@protonmail.com>2023-04-27 23:51:14 +0200
commitcee712105850ac3385cd0091a923438167433f9f (patch)
tree4a5274b21d8b7f938c0d0ce18736d3f2993b11b1 /src/ARMeilleure/Decoders/OpCodeMemImm.cs
parentcd124bda587ef09668a971fa1cac1c3f0cfc9f21 (diff)
Move solution and projects to src
Diffstat (limited to 'src/ARMeilleure/Decoders/OpCodeMemImm.cs')
-rw-r--r--src/ARMeilleure/Decoders/OpCodeMemImm.cs53
1 files changed, 53 insertions, 0 deletions
diff --git a/src/ARMeilleure/Decoders/OpCodeMemImm.cs b/src/ARMeilleure/Decoders/OpCodeMemImm.cs
new file mode 100644
index 00000000..d6ed2282
--- /dev/null
+++ b/src/ARMeilleure/Decoders/OpCodeMemImm.cs
@@ -0,0 +1,53 @@
+namespace ARMeilleure.Decoders
+{
+ class OpCodeMemImm : OpCodeMem
+ {
+ public long Immediate { get; protected set; }
+ public bool WBack { get; protected set; }
+ public bool PostIdx { get; protected set; }
+ protected bool Unscaled { get; }
+
+ private enum MemOp
+ {
+ Unscaled = 0,
+ PostIndexed = 1,
+ Unprivileged = 2,
+ PreIndexed = 3,
+ Unsigned
+ }
+
+ public new static OpCode Create(InstDescriptor inst, ulong address, int opCode) => new OpCodeMemImm(inst, address, opCode);
+
+ public OpCodeMemImm(InstDescriptor inst, ulong address, int opCode) : base(inst, address, opCode)
+ {
+ Extend64 = ((opCode >> 22) & 3) == 2;
+ WBack = ((opCode >> 24) & 1) == 0;
+
+ // The type is not valid for the Unsigned Immediate 12-bits encoding,
+ // because the bits 11:10 are used for the larger Immediate offset.
+ MemOp type = WBack ? (MemOp)((opCode >> 10) & 3) : MemOp.Unsigned;
+
+ PostIdx = type == MemOp.PostIndexed;
+ Unscaled = type == MemOp.Unscaled ||
+ type == MemOp.Unprivileged;
+
+ // Unscaled and Unprivileged doesn't write back,
+ // but they do use the 9-bits Signed Immediate.
+ if (Unscaled)
+ {
+ WBack = false;
+ }
+
+ if (WBack || Unscaled)
+ {
+ // 9-bits Signed Immediate.
+ Immediate = (opCode << 11) >> 23;
+ }
+ else
+ {
+ // 12-bits Unsigned Immediate.
+ Immediate = ((opCode >> 10) & 0xfff) << Size;
+ }
+ }
+ }
+} \ No newline at end of file