7159 - explicitly use 'return' everywhere

https://github.com/akkartik/mu/issues/45#issuecomment-719990879, task 2.

4 files changed, 18 insertions, 14 deletions

diff --git a/apps/raytracing/1.mu b/apps/raytracing/1.mu
index 539332ea..fbc76f1d 100644
--- a/apps/raytracing/1.mu
+++ b/apps/raytracing/1.mu
@@ -7,7 +7,7 @@
 #   $ ./translate_mu apps/raytracing/1.mu
 #   $ ./a.elf > 1.ppm
 
-fn main -> exit-status/ebx: int {
+fn main -> _/ebx: int {
   print-string 0, "P3\n256 256\n255\n"
   var j/ecx: int <- copy 0xff
   {
@@ -27,5 +27,5 @@ fn main -> exit-status/ebx: int {
     j <- decrement
     loop
   }
-  exit-status <- copy 1
+  return 0
 }
diff --git a/apps/raytracing/2.mu b/apps/raytracing/2.mu
index 69bc9a40..e23ce3b4 100644
--- a/apps/raytracing/2.mu
+++ b/apps/raytracing/2.mu
@@ -6,7 +6,7 @@
 #   $ ./translate_mu apps/raytracing/2.mu
 #   $ ./a.elf > 2.ppm
 
-fn main -> exit-status/ebx: int {
+fn main -> _/ebx: int {
   print-string 0, "P3\n256 256\n255\n"
   var _four/edx: int <- copy 4
   var four/xmm1: float <- convert _four
@@ -47,7 +47,7 @@ fn main -> exit-status/ebx: int {
     j <- decrement
     loop
   }
-  exit-status <- copy 1
+  return 0
 }
 
 type rgb {
diff --git a/apps/raytracing/3.mu b/apps/raytracing/3.mu
index acc2df33..5b87f344 100644
--- a/apps/raytracing/3.mu
+++ b/apps/raytracing/3.mu
@@ -59,7 +59,7 @@ fn ray-color _in: (addr ray), _out: (addr rgb) {
 #?   print-string 0, "\n"
 }
 
-fn main -> exit-status/ebx: int {
+fn main -> _/ebx: int {
 
   # image
   #   width = 400
@@ -221,7 +221,7 @@ fn main -> exit-status/ebx: int {
     j <- decrement
     loop
   }
-  exit-status <- copy 1
+  return 0
 }
 
 type ray {
@@ -457,18 +457,19 @@ fn vec3-unit in: (addr vec3), out: (addr vec3) {
   vec3-scale-down out, len
 }
 
-fn vec3-length v: (addr vec3) -> result/xmm0: float {
-  result <- vec3-length-squared v
+fn vec3-length v: (addr vec3) -> _/xmm0: float {
+  var result/xmm0: float <- vec3-length-squared v
   result <- square-root result
+  return result
 }
 
-fn vec3-length-squared _v: (addr vec3) -> result/xmm0: float {
+fn vec3-length-squared _v: (addr vec3) -> _/xmm0: float {
   var v/esi: (addr vec3) <- copy _v
   # result = v.x * v.x
   var src/eax: (addr float) <- get v, x
   var tmp/xmm1: float <- copy *src
   tmp <- multiply tmp
-  result <- copy tmp
+  var result/xmm0: float <- copy tmp
   # result += v.y * v.y
   src <- get v, y
   tmp <- copy *src
@@ -479,4 +480,5 @@ fn vec3-length-squared _v: (addr vec3) -> result/xmm0: float {
   tmp <- copy *src
   tmp <- multiply tmp
   result <- add tmp
+  return result
 }
diff --git a/apps/raytracing/vec.mu b/apps/raytracing/vec.mu
index ce745a15..c93bab91 100644
--- a/apps/raytracing/vec.mu
+++ b/apps/raytracing/vec.mu
@@ -102,18 +102,19 @@ fn vec3-unit in: (addr vec3), out: (addr vec3) {
   vec3-scale-down out, len
 }
 
-fn vec3-length v: (addr vec3) -> result/xmm0: float {
-  result <- vec3-length-squared v
+fn vec3-length v: (addr vec3) -> _/xmm0: float {
+  var result/xmm0: float <- vec3-length-squared v
   result <- square-root result
+  return result
 }
 
-fn vec3-length-squared _v: (addr vec3) -> result/xmm0: float {
+fn vec3-length-squared _v: (addr vec3) -> _/xmm0: float {
   var v/esi: (addr vec3) <- copy _v
   # result = v.x * v.x
   var src/eax: (addr float) <- get v, x
   var tmp/xmm1: float <- copy *src
   tmp <- multiply tmp
-  result <- copy tmp
+  var result/xmm0: float <- copy tmp
   # result += v.y * v.y
   src <- get v, y
   tmp <- copy *src
@@ -124,6 +125,7 @@ fn vec3-length-squared _v: (addr vec3) -> result/xmm0: float {
   tmp <- copy *src
   tmp <- multiply tmp
   result <- add tmp
+  return result
 }
 
 fn vec3-dot _v1: (addr vec3), _v2: (addr vec3) -> result/xmm0: float {