Optimize more easy multiplications by constants.
Rather than make these changes in the libraries (*10 being a common case),
let's do them once and for all in the JIT.
The 2^n-1 case could be better if we generated RSB instructions, but the
current "fake" RSB is still better than a full multiply.
Thumb doesn't support reg/reg/reg/shift instructions, so we can't optimize
the "population count <= 2" cases (such as *10) there.
Tested on sholes, passion, and passion-running-sapphire (and visually
inspected to check we weren't trying to generate Thumb2 instructions there).
Also tested with the self-verifier.
diff --git a/vm/compiler/codegen/arm/ArmLIR.h b/vm/compiler/codegen/arm/ArmLIR.h
index b329aed..7d26221 100644
--- a/vm/compiler/codegen/arm/ArmLIR.h
+++ b/vm/compiler/codegen/arm/ArmLIR.h
@@ -706,7 +706,7 @@
/*
* Each instance of this struct holds a pseudo or real LIR instruction:
- * - pesudo ones (eg labels and marks) and will be discarded by the assembler.
+ * - pseudo ones (eg labels and marks) and will be discarded by the assembler.
* - real ones will be assembled into Thumb instructions.
*
* Machine resources are encoded into a 64-bit vector, where the encodings are