Refactor PUSH/POP in ARM assemblers.

src/IceRegistersARM32.h

Index: src/IceRegistersARM32.h
diff --git a/src/IceRegistersARM32.h b/src/IceRegistersARM32.h
index 0caa9ccdf4e225ccfd0e40bcd6838c36bbb4011b..2434a4d29d3acdd64335e3518e808f76b4ca1bc7 100644
--- a/src/IceRegistersARM32.h
+++ b/src/IceRegistersARM32.h
@@ -152,6 +152,21 @@ public:
     return GPRRegister(Table[RegNum].Encoding);
   }
 
+  static inline SizeT getNumGPRs() {

[John, 2016/01/11 13:40:36]

You don't need this method if you use Table[] -- see the comment below.

[Karl, 2016/01/11 17:59:44]

This form is used because it allows it to be a constexpr, and using local
variables (to do the counting) is not allowed till c++ 14.

+    return 0
+#define X(val, encode, name, cc_arg, scratch, preserved, stackptr, frameptr,   \
+          isGPR, isInt, isI64Pair, isFP32, isFP64, isVec128, alias_init)       \
+  +(isGPR)
+        REGARM32_TABLE
+#undef X
+        ;
+  }
+
+  static inline IceString getGPRName(SizeT RegNum) {
+    assert(RegNum <= getNumGPRs());

[Jim Stichnoth, 2016/01/10 18:22:00]

Should this be "<" instead of "<=" ?

(same comment for below)

[John, 2016/01/11 13:40:36]

Now that we have RegARM32::Table[], this should be implemented (IMO) as:

  assert(RegNum < Reg_NUM);
  assert(Table[RegNum].IsGPR);
  return Table[RegNum].Name;

(all of these functions should be re-defined to use Table[], but that should be
done in a separate CL)

[Karl, 2016/01/11 17:59:44]

As far as John's comment, I was making too many assumptions. Simplifying.

Also, I agree that the rest of the file should be cleaned up to use the table.

[Karl, 2016/01/11 17:59:44]

Done.

+    return getRegName(Reg_GPR_First + RegNum);
+  }
+
   static inline GPRRegister getI64PairFirstGPRNum(int32_t RegNum) {
     assert(Reg_I64PAIR_First <= RegNum);
     assert(RegNum <= Reg_I64PAIR_Last);
@@ -173,7 +188,18 @@ public:
   }
 
   static inline SizeT getNumSRegs() {

[John, 2016/01/11 13:40:36]

can you remove inline here, and add constexpr?

static constexpr SizeT getNumSRegs()

?

[Karl, 2016/01/11 17:59:44]

Done.

-    return Reg_SREG_Last + 1 - Reg_SREG_First;
+    return 0
+#define X(val, encode, name, cc_arg, scratch, preserved, stackptr, frameptr,   \
+          isGPR, isInt, isI64Pair, isFP32, isFP64, isVec128, alias_init)       \
+  +(isFP32)
+        REGARM32_TABLE
+#undef X
+        ;
+  }
+
+  static inline IceString getSRegName(SizeT RegNum) {
+    assert(RegNum <= getNumSRegs());

[John, 2016/01/11 13:40:36]

Please use Table[].

  assert(RegNum < Reg_NUM);
  assert(Table[RegNum].IsFP32);
  return Table[RegNum].Name;

[Karl, 2016/01/11 17:59:44]

Done.

+    return getRegName(Reg_SREG_First + RegNum);
   }
 
   static inline SRegister getEncodedSReg(int32_t RegNum) {