SubZero: Adding support for all Reg pairs in getI64PairFirst/SecondGPRNum

src/IceRegistersMIPS32.h

Index: src/IceRegistersMIPS32.h
diff --git a/src/IceRegistersMIPS32.h b/src/IceRegistersMIPS32.h
index 2e39ce683ebfba19aca76490420e3ffb7cb73265..b54a6e9e4fe54dee118e8b857bd4bb830c8c451b 100644
--- a/src/IceRegistersMIPS32.h
+++ b/src/IceRegistersMIPS32.h
@@ -89,22 +89,32 @@ static inline bool isFPRReg(RegNumT RegNum) {
 
 const char *getRegName(RegNumT RegNum);
 
-static inline RegNumT getI64PairFirstGPRNum(RegNumT RegNum) {
-  // For now it works only for argument register pairs
-  // TODO(mohit.bhakkad): Change this to support all the register pairs once we
-  // have table-driven approach ready
-  assert(RegNum == Reg_A0A1 || RegNum == Reg_A2A3);
-  return (RegNum == RegMIPS32::Reg_A0A1) ? RegMIPS32::Reg_A0
-                                         : RegMIPS32::Reg_A2;
+static inline RegNumT get64PairFirstRegNum(RegNumT RegNum) {
+  assert(unsigned(RegNum) >= Reg_I64PAIR_First &&

[Jim Stichnoth, 2016/08/01 20:14:29]

Instead of:
  assert(a && b);
do:
  assert(a);
  assert(b);
in order to get better precision on an assertion failure.

(here and below)

+         unsigned(RegNum) <= Reg_F64PAIR_Last);
+  if (unsigned(RegNum) >= Reg_F64PAIR_First &&
+      unsigned(RegNum) <= Reg_F64PAIR_Last)
+    return RegNumT::fixme(((RegNum - Reg_F64PAIR_First) * 2) +
+                          unsigned(Reg_FPR_First));
+  else if (unsigned(RegNum) >= Reg_I64PAIR_First &&

[Jim Stichnoth, 2016/08/01 20:14:29]

change "else if" to "if" because of the unconditional return in the "if" branch.

(here and below)

+           unsigned(RegNum) <= Reg_T8T9)
+    return RegNumT::fixme(((RegNum - Reg_I64PAIR_First) * 2) +
+                          unsigned(Reg_V0));
+  return RegMIPS32::Reg_LO;
 }
 
-static inline RegNumT getI64PairSecondGPRNum(RegNumT RegNum) {
-  // For now it works only for argument register pairs
-  // TODO(mohit.bhakkad): Change this to support all the register pairs once we
-  // have table-driven approach ready
-  assert(RegNum == Reg_A0A1 || RegNum == Reg_A2A3);
-  return (RegNum == RegMIPS32::Reg_A0A1) ? RegMIPS32::Reg_A1
-                                         : RegMIPS32::Reg_A3;
+static inline RegNumT get64PairSecondRegNum(RegNumT RegNum) {
+  assert(unsigned(RegNum) >= Reg_I64PAIR_First &&
+         unsigned(RegNum) <= Reg_F64PAIR_Last);
+  if (unsigned(RegNum) >= Reg_F64PAIR_First &&
+      unsigned(RegNum) <= Reg_F64PAIR_Last)
+    return RegNumT::fixme(((RegNum - Reg_F64PAIR_First) * 2) +
+                          unsigned(Reg_FPR_First) + 1);
+  else if (unsigned(RegNum) >= Reg_I64PAIR_First &&
+           unsigned(RegNum) <= Reg_T8T9)
+    return RegNumT::fixme(((RegNum - Reg_I64PAIR_First) * 2) +
+                          unsigned(Reg_V1));
+  return RegMIPS32::Reg_HI;
 }
 
 } // end of namespace RegMIPS32