feat(parser): macro expansion, conditionals and include splicing with -I

Assisted-by: GLM 5.3 Flash

docs/man/gasm-asm.1

@@ -2,7 +2,7 @@
 .SH NAME
 gasm-asm \- assemble Plan 9 assembly without the Go toolchain
 .SH SYNOPSIS
-.B gasm asm [\-\-format raw|elf|goobj] [\-p pkg] [\-GOARCH arch] [\-o out] <file>
+.B gasm asm [\-\-format raw|elf|goobj] [\-I dir] [\-p pkg] [\-GOARCH arch] [\-o out] <file>
 .SH DESCRIPTION
 Assemble FILE without the Go toolchain: every TEXT function is encoded
 to machine code and printed as a hex dump.  Supported architectures:
@@ -47,6 +47,10 @@ functions link too.
 .B \-\-format \fIraw|elf|goobj\fR
 Output format; the default is raw.
 .TP
+.B \-I \fIdir\fR
+Directory to search for #include files; may be repeated, searched in
+order after the source directory.
+.TP
 .B \-p \fIpkg\fR
 Package path for --format goobj, qualifying the exported symbols.
 .TP

docs/man/gasm-audit-instructions.1

@@ -2,7 +2,7 @@
 .SH NAME
 gasm-audit-instructions \- diff the encoder against the Go toolchain, or measure a corpus
 .SH SYNOPSIS
-.B gasm audit\-instructions [\-\-corpus [\fIdir\fR]] [amd64|arm64|riscv64|loong64]
+.B gasm audit\-instructions [\-\-corpus [\fIdir\fR]] [\-I dir] [amd64|arm64|riscv64|loong64]
 .SH DESCRIPTION
 Compare the gasm encoder for the given architecture (default amd64)
 against
@@ -38,6 +38,12 @@ second.
 .B \-\-corpus [\fIdir\fR]
 Assemble a corpus of .s files and report pass rates and failure
 reasons.
+.TP
+.B \-I \fIdir\fR
+Directory to search for #include files; may be repeated, searched in
+order after the source directory.  A corpus run whose files include
+toolchain headers (such as GOROOT/pkg/include) needs it, the same -I a
+toolchain comparison takes.
 .SH EXIT STATUS
 The mnemonic-diff mode reports through its output and exits 0; a failed
 probe or an unknown architecture exits non-zero.

docs/man/gasm-diff.1

@@ -2,7 +2,7 @@
 .SH NAME
 gasm-diff \- compare the machine code of two assembly files
 .SH SYNOPSIS
-.B gasm diff [\-GOARCH arch] <file1.s> <file2.s>
+.B gasm diff [\-GOARCH arch] [\-I dir] <file1.s> <file2.s>
 .SH DESCRIPTION
 Compare the machine code produced by assembling two files.  Shows which
 functions differ and the byte-level differences.  Useful for verifying
@@ -20,6 +20,10 @@ pairs two variants regardless of suffix.
 Target architecture for both files: amd64, arm64, riscv64 or loong64;
 overrides the file-name suffixes.
 .TP
+.B \-I \fIdir\fR
+Directory to search for #include files; may be repeated, searched in
+order after the source directory.
+.TP
 .B \-\-map \fIspec\fR
 Comma-separated old=new pairs to match functions with different names.
 .SH EXIT STATUS