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+{{- /*
+instruction - Standardized instruction reference card, following the layout
+used in the Patt & Patel textbook: mnemonic title, short description, assembler
+formats, encoding diagram, high-level operation, and usage examples.
+
+@param {string} mnemonic       Instruction mnemonic(s), comma-separated if more
+                               than one (e.g. "ADD" or "JSR, JSRR").
+@param {string} short          Short two-to-three word description (e.g.
+                               "Addition").
+@param {string} formats        Assembler format(s). Use a backtick-quoted
+                               string for multiple lines.
+@param {string} encoding       Filename of the encoding diagram
+@param {string} encoding-dark  Optional dark mode variant of the encoding
+                               diagram. If set, `encoding` is only shown in
+                               light mode and this is shown in dark mode.
+@param {string} operation      High-level operation, typically pseudo-C. Use a
+                               backtick-quoted string for multiple lines.
+@param {string} examples       Usage examples in LC-2 assembly. Use a
+                               backtick-quoted string for multiple lines.
+
+@example {{% instruction
+  mnemonic="ADD"
+  short="Addition"
+
+  formats=`ADD DR, SR1, SR2
+ADD DR, SR1, imm5`
+
+  encoding="add.drawio.png"
+  encoding-dark="add-dark.drawio.png"
+
+  operation=`if (bit[5] == 0) {
+    DR = SR1 + SR2;
+} else {
+    DR = SR1 + SEXT(imm5);
+}
+
+setcc(DR);`
+
+  examples=`ADD R2, R3, R4    ;  R2 ← R3 + R4
+ADD R2, R3, #7    ;  R2 ← R3 + 7`
+
+%}}
+If bit [5] is 0, the second-source operand is obtained from SR2. If bit [5] is
+1, the second-source operand is obtained by sign-extending the imm5 field to 16
+bits. In both cases, the second source operand is added to the contents of SR1,
+and the result stored in DR. The condition codes are set, based on whether the
+result is negative, zero, or positive.
+{{% /instruction %}}
+
+*/ -}}
+
+{{- $mnemonic     := .Get "mnemonic" -}}
+{{- $short        := .Get "short" -}}
+{{- $formats      := .Get "formats" -}}
+{{- $encoding     := .Get "encoding" -}}
+{{- $encodingDark := .Get "encoding-dark" -}}
+{{- $operation    := .Get "operation" -}}
+{{- $examples     := .Get "examples" -}}
+{{- $description  := .Inner -}}
+
+### {{ $mnemonic }}
+
+> {{ $short }}
+
+<h4>Assembler Formats</h4>
+
+```
+{{ $formats }}
+```
+
+<h4>Encoding</h4>
+
+{{ if $encodingDark }}
+<img src="{{ $encoding }}" alt="{{ $mnemonic }} instruction encoding" class="hx:dark:hidden">
+<img src="{{ $encodingDark }}" alt="{{ $mnemonic }} instruction encoding" class="hx:hidden hx:dark:block">
+{{ else }}
+<img src="{{ $encoding }}" alt="{{ $mnemonic }} instruction encoding">
+{{ end }}
+
+<h4>Operation</h4>
+
+```c
+{{ $operation }}
+```
+
+<h4>Description</h4>
+
+{{ $description }}
+
+<h4>Examples</h4>
+
+```
+{{ $examples }}
+```