diff --git a/cpclib-basm/pgo.sh b/cpclib-basm/pgo.sh
new file mode 100755
index 00000000..80213103
--- /dev/null
+++ b/cpclib-basm/pgo.sh
@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+
+set -e
+
+
+PROGRAM="basm"
+
+# STEP 0: Make sure there is no left-over profiling data from previous runs
+rm -rf /tmp/pgo-data || true
+
+# STEP 1: Build the instrumented binaries
+RUSTFLAGS="-Cprofile-generate=/tmp/pgo-data" \
+  cargo build --release
+
+# STEP 2: Run the instrumented binaries with some typical data
+../target/release/$PROGRAM ../../z80_assemblers_benchmark/z80/include_files.asm > /dev/null
+../target/release/$PROGRAM ./tests/asm/roudoudou/rasm_sprites.asm  > /dev/null
+
+# STEP 3: Merge the `.profraw` files into a `.profdata` file
+llvm-profdata merge -o /tmp/pgo-data/merged.profdata /tmp/pgo-data
+
+# STEP 4: Use the `.profdata` file for guiding optimizations
+RUSTFLAGS="-Cprofile-use=/tmp/pgo-data/merged.profdata" \
+    cargo build --release
\ No newline at end of file
diff --git a/cpclib-basm/tests/asm/disc/save_hfe.asm b/cpclib-basm/tests/asm/disc/save_hfe.asm
new file mode 100644
index 00000000..222100ba
--- /dev/null
+++ b/cpclib-basm/tests/asm/disc/save_hfe.asm
@@ -0,0 +1,8 @@
+	org 0x4000
+BINARY_START
+	run $
+	ld a, 'A' : call 0xbb5a
+	jp $
+BINARY_STOP
+
+	save "test", BINARY_START, BINARY_STOP-BINARY_START, HFE, "saved.hfe"
\ No newline at end of file
diff --git a/cpclib-basm/tests/asm/disc/saved.hfe b/cpclib-basm/tests/asm/disc/saved.hfe
new file mode 100644
index 00000000..e6186f7e
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diff --git a/cpclib-basm/tests/asm/rasm_comparison/basm.sna b/cpclib-basm/tests/asm/rasm_comparison/basm.sna
new file mode 100644
index 00000000..c4a24835
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diff --git a/cpclib-basm/tests/asm/rasm_comparison/basm_withbrks.sna b/cpclib-basm/tests/asm/rasm_comparison/basm_withbrks.sna
new file mode 100644
index 00000000..38e159be
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diff --git a/cpclib-basm/tests/asm/rasm_comparison/basm_withoutbrks.sna b/cpclib-basm/tests/asm/rasm_comparison/basm_withoutbrks.sna
new file mode 100644
index 00000000..b0612fca
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diff --git a/cpclib-basm/tests/asm/rasm_comparison/rasm.dsk b/cpclib-basm/tests/asm/rasm_comparison/rasm.dsk
new file mode 100644
index 00000000..117b8e09
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diff --git a/cpclib-basm/tests/asm/rasm_comparison/rasm.sna b/cpclib-basm/tests/asm/rasm_comparison/rasm.sna
new file mode 100644
index 00000000..07e5a7c5
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diff --git a/cpclib-basm/tests/asm/rasm_comparison/rasm_master.sna b/cpclib-basm/tests/asm/rasm_comparison/rasm_master.sna
new file mode 100644
index 00000000..07e5a7c5
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diff --git a/cpclib-basm/tests/asm/rasm_comparison/save_dsk.asm b/cpclib-basm/tests/asm/rasm_comparison/save_dsk.asm
new file mode 100644
index 00000000..8137d0ee
--- /dev/null
+++ b/cpclib-basm/tests/asm/rasm_comparison/save_dsk.asm
@@ -0,0 +1,8 @@
+
+	org 0x4000
+BINARY_START
+	run $
+	jp $
+BINARY_STOP
+
+	save "test", BINARY_START, BINARY_STOP-BINARY_START, DSK, "saved.dsk"
\ No newline at end of file
diff --git a/cpclib-basm/tests/asm/rasm_comparison/save_sna.asm b/cpclib-basm/tests/asm/rasm_comparison/save_sna.asm
new file mode 100644
index 00000000..ab1a4805
--- /dev/null
+++ b/cpclib-basm/tests/asm/rasm_comparison/save_sna.asm
@@ -0,0 +1,16 @@
+	; cargo run -- save_sna.asm  --nochunk BRKS --sna -o basm.sna
+	; to be compared with 
+	; rasm -sb -ss  save_sna.asm -o rasm
+
+
+	BUILDSNA
+	BANKSET 0
+
+	org 0x1234
+BINARY_START
+	run $
+START
+	BREAKPOINT
+	jp $
+	BREAKPOINT
+BINARY_STOP
\ No newline at end of file
diff --git a/cpclib-basm/tests/asm/rasm_comparison/saved.hfe b/cpclib-basm/tests/asm/rasm_comparison/saved.hfe
new file mode 100644
index 00000000..25ff6fca
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