From 0d2f423cec902068b76fa6d0e4905a13c75963bc Mon Sep 17 00:00:00 2001
From: bcarlet <8906114+bcarlet@users.noreply.github.com>
Date: Tue, 29 Aug 2023 23:08:24 -0400
Subject: [PATCH 1/2] Add Hanoi benchmark

---
 benchmarks/core/hanoi.bril | 26 ++++++++++++++++++++++++++
 benchmarks/core/hanoi.out  |  7 +++++++
 benchmarks/core/hanoi.prof |  1 +
 docs/tools/bench.md        |  2 ++
 4 files changed, 36 insertions(+)
 create mode 100644 benchmarks/core/hanoi.bril
 create mode 100644 benchmarks/core/hanoi.out
 create mode 100644 benchmarks/core/hanoi.prof

diff --git a/benchmarks/core/hanoi.bril b/benchmarks/core/hanoi.bril
new file mode 100644
index 000000000..c32df92d5
--- /dev/null
+++ b/benchmarks/core/hanoi.bril
@@ -0,0 +1,26 @@
+# Three-disk Tower of Hanoi puzzle.
+#
+# Moves are printed in order, one on each line, where a move `src dst` indicates
+# that the top disk from rod `src` should be moved to rod `dst`.
+
+@hanoi (disk: int, src: int, dst: int, spare: int) {
+  zero: int = const 0;
+  nonneg: bool = ge disk zero;
+  br nonneg .then .else;
+.then:
+  one: int = const 1;
+  above: int = sub disk one;
+  call @hanoi above src spare dst;
+  print src dst;
+  call @hanoi above spare dst src;
+.else:
+  ret;
+}
+
+@main {
+  disk: int = const 2;
+  src: int = const 0;
+  dst: int = const 2;
+  spare: int = const 1;
+  call @hanoi disk src dst spare;
+}
diff --git a/benchmarks/core/hanoi.out b/benchmarks/core/hanoi.out
new file mode 100644
index 000000000..57c7c1bc4
--- /dev/null
+++ b/benchmarks/core/hanoi.out
@@ -0,0 +1,7 @@
+0 2
+0 1
+2 1
+0 2
+1 0
+1 2
+0 2
diff --git a/benchmarks/core/hanoi.prof b/benchmarks/core/hanoi.prof
new file mode 100644
index 000000000..a02ef5fe2
--- /dev/null
+++ b/benchmarks/core/hanoi.prof
@@ -0,0 +1 @@
+total_dyn_inst: 100
diff --git a/docs/tools/bench.md b/docs/tools/bench.md
index 4cbcf3906..bc1602c58 100644
--- a/docs/tools/bench.md
+++ b/docs/tools/bench.md
@@ -28,6 +28,7 @@ The current benchmarks are:
 * `fizz-buzz`: The infamous [programming test][fizzbuzz].
 * `function_call`: For benchmarking the overhead of simple function calls.
 * `gcd`: Calculate Greatest Common Divisor (GCD) of two input positive integer using [Euclidean algorithm][euclidean_into].
+* `hanoi`: Print the solution to the 3-disk [Tower of Hanoi][hanoi] puzzle.
 * `loopfact`: Compute *n!* imperatively using a loop.
 * `mandelbrot`: Generates a really low resolution, ascii, [mandelbrot set][mandelbrot].
 * `mat-inv` : Calculates the inverse of a 3x3 matrix and prints it out.
@@ -78,3 +79,4 @@ Credit for several of these benchmarks goes to Alexa VanHattum and Gregory Yaune
 [uparrow]: https://en.wikipedia.org/wiki/Knuth%27s_up-arrow_notation
 [riemann]: https://en.wikipedia.org/wiki/Riemann_sum
 [mandelbrot]: https://en.wikipedia.org/wiki/Mandelbrot_set
+[hanoi]: https://en.wikipedia.org/wiki/Tower_of_Hanoi

From 24f2cc5d82fd220aeda7464c49b8af28fca037cc Mon Sep 17 00:00:00 2001
From: bcarlet <8906114+bcarlet@users.noreply.github.com>
Date: Wed, 30 Aug 2023 11:52:59 -0400
Subject: [PATCH 2/2] Generalize to n disks

---
 benchmarks/core/hanoi.bril | 21 +++++++++++----------
 benchmarks/core/hanoi.prof |  2 +-
 docs/tools/bench.md        |  2 +-
 3 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/benchmarks/core/hanoi.bril b/benchmarks/core/hanoi.bril
index c32df92d5..f60e5389b 100644
--- a/benchmarks/core/hanoi.bril
+++ b/benchmarks/core/hanoi.bril
@@ -1,15 +1,16 @@
-# Three-disk Tower of Hanoi puzzle.
+# Tower of Hanoi puzzle.
 #
-# Moves are printed in order, one on each line, where a move `src dst` indicates
-# that the top disk from rod `src` should be moved to rod `dst`.
+# Input:  Number of disks.
+# Output: Each move in order, one on each line, where a move `src dst` indicates
+#         that the top disk from rod `src` should be moved to rod `dst`.
 
-@hanoi (disk: int, src: int, dst: int, spare: int) {
+@hanoi (disks: int, src: int, dst: int, spare: int) {
   zero: int = const 0;
-  nonneg: bool = ge disk zero;
-  br nonneg .then .else;
+  pos: bool = gt disks zero;
+  br pos .then .else;
 .then:
   one: int = const 1;
-  above: int = sub disk one;
+  above: int = sub disks one;
   call @hanoi above src spare dst;
   print src dst;
   call @hanoi above spare dst src;
@@ -17,10 +18,10 @@
   ret;
 }
 
-@main {
-  disk: int = const 2;
+# ARGS: 3
+@main (disks: int) {
   src: int = const 0;
   dst: int = const 2;
   spare: int = const 1;
-  call @hanoi disk src dst spare;
+  call @hanoi disks src dst spare;
 }
diff --git a/benchmarks/core/hanoi.prof b/benchmarks/core/hanoi.prof
index a02ef5fe2..b50ba70bd 100644
--- a/benchmarks/core/hanoi.prof
+++ b/benchmarks/core/hanoi.prof
@@ -1 +1 @@
-total_dyn_inst: 100
+total_dyn_inst: 99
diff --git a/docs/tools/bench.md b/docs/tools/bench.md
index bc1602c58..cac28a6d6 100644
--- a/docs/tools/bench.md
+++ b/docs/tools/bench.md
@@ -28,7 +28,7 @@ The current benchmarks are:
 * `fizz-buzz`: The infamous [programming test][fizzbuzz].
 * `function_call`: For benchmarking the overhead of simple function calls.
 * `gcd`: Calculate Greatest Common Divisor (GCD) of two input positive integer using [Euclidean algorithm][euclidean_into].
-* `hanoi`: Print the solution to the 3-disk [Tower of Hanoi][hanoi] puzzle.
+* `hanoi`: Print the solution to the *n*-disk [Tower of Hanoi][hanoi] puzzle.
 * `loopfact`: Compute *n!* imperatively using a loop.
 * `mandelbrot`: Generates a really low resolution, ascii, [mandelbrot set][mandelbrot].
 * `mat-inv` : Calculates the inverse of a 3x3 matrix and prints it out.