diff --git a/include/mtl/armv4t/asm/math.s b/include/mtl/armv4t/asm/math.s
index 9333c3e..a3f38b2 100644
--- a/include/mtl/armv4t/asm/math.s
+++ b/include/mtl/armv4t/asm/math.s
@@ -7,7 +7,8 @@
  * 0xCCCCCCCD >> 35 approximately equals 0.1
  * Performs a 64 bit multiply of 0xCCCCCCCD and rx, shifts the high 32 bits
  * by 3, and discards the low bits. This results in a division by 10 that
- * works for all unsigned values of rx
+ * works for all unsigned values of rx. This satifies the constraints of
+ * the Granlund-Montgomery integer division algorithm.
  */
 .macro udiv10 rd, rx, rt
 	ldr	\rt, =0xCCCCCCCD
@@ -33,10 +34,20 @@
 	lsrs	\rd, $13
 .endm
 
+/*
+ * When using the Granlund-Montgomery integer division algorithm, the magic
+ * number produced does not fit inside the int32 range. GM produces:
+ *   m = 0x14F8B588F
+ *   k = 17
+ *
+ * This division uses the output produces by clang for a division by 100000.
+ * I don't understand why it works, but it does.
+ */
 .macro udiv100000 rd, rx, rt
-	ldr	\rt, =0x29f17
+	lsr	\rx, $5
+	ldr	\rt, =0xA7C5AC5
 	umull	\rt, \rd, \rx, \rt
-	lsrs	\rd, $2
+	lsrs	\rd, $7
 .endm
 
 .macro udiv1000000 rd, rx, rt
@@ -57,10 +68,14 @@
 	lsrs	\rd, $25
 .endm
 
+/*
+ * Same situation as udiv100000
+ */
 .macro udiv1000000000 rd, rx, rt
-	ldr	\rt, =0x44b82fa1
+	lsr	\rx, $9
+	ldr	\rt, =0x44B83
 	umull	\rt, \rd, \rx, \rt
-	lsrs	\rd, $28
+	lsrs	\rd, $7
 .endm
 
 /*