Do not force indirect tailcall through fixed registers: eax, r11. Add support to allow loads to be folded to tail call instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98465 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86InstrInfo.cpp b/lib/Target/X86/X86InstrInfo.cpp
index 4fd91bb..139a905 100644
--- a/lib/Target/X86/X86InstrInfo.cpp
+++ b/lib/Target/X86/X86InstrInfo.cpp
@@ -266,6 +266,7 @@
     { X86::MOV16rr,     X86::MOV16mr, 0, 0 },
     { X86::MOV32ri,     X86::MOV32mi, 0, 0 },
     { X86::MOV32rr,     X86::MOV32mr, 0, 0 },
+    { X86::MOV32rr_TC,  X86::MOV32mr_TC, 0, 0 },
     { X86::MOV64ri32,   X86::MOV64mi32, 0, 0 },
     { X86::MOV64rr,     X86::MOV64mr, 0, 0 },
     { X86::MOV8ri,      X86::MOV8mi, 0, 0 },
@@ -301,6 +302,7 @@
     { X86::SETPr,       X86::SETPm, 0, 0 },
     { X86::SETSr,       X86::SETSm, 0, 0 },
     { X86::TAILJMPr,    X86::TAILJMPm, 1, 0 },
+    { X86::TAILJMPr64,  X86::TAILJMPm64, 1, 0 },
     { X86::TEST16ri,    X86::TEST16mi, 1, 0 },
     { X86::TEST32ri,    X86::TEST32mi, 1, 0 },
     { X86::TEST64ri32,  X86::TEST64mi32, 1, 0 },
@@ -376,6 +378,7 @@
     { X86::Int_UCOMISSrr,   X86::Int_UCOMISSrm, 0 },
     { X86::MOV16rr,         X86::MOV16rm, 0 },
     { X86::MOV32rr,         X86::MOV32rm, 0 },
+    { X86::MOV32rr_TC,      X86::MOV32rm_TC, 0 },
     { X86::MOV64rr,         X86::MOV64rm, 0 },
     { X86::MOV64toPQIrr,    X86::MOVQI2PQIrm, 0 },
     { X86::MOV64toSDrr,     X86::MOV64toSDrm, 0 },
@@ -675,6 +678,8 @@
   case X86::MOV16rr:
   case X86::MOV32rr: 
   case X86::MOV64rr:
+  case X86::MOV32rr_TC: 
+  case X86::MOV64rr_TC:
 
   // FP Stack register class copies
   case X86::MOV_Fp3232: case X86::MOV_Fp6464: case X86::MOV_Fp8080:
@@ -1901,6 +1906,10 @@
       Opc = X86::MOV16rr;
     } else if (CommonRC == &X86::GR8_NOREXRegClass) {
       Opc = X86::MOV8rr;
+    } else if (CommonRC == &X86::GR64_TCRegClass) {
+      Opc = X86::MOV64rr_TC;
+    } else if (CommonRC == &X86::GR32_TCRegClass) {
+      Opc = X86::MOV32rr_TC;
     } else if (CommonRC == &X86::RFP32RegClass) {
       Opc = X86::MOV_Fp3232;
     } else if (CommonRC == &X86::RFP64RegClass || CommonRC == &X86::RSTRegClass) {
@@ -2038,6 +2047,10 @@
     Opc = X86::MOV16mr;
   } else if (RC == &X86::GR8_NOREXRegClass) {
     Opc = X86::MOV8mr;
+  } else if (RC == &X86::GR64_TCRegClass) {
+    Opc = X86::MOV64mr_TC;
+  } else if (RC == &X86::GR32_TCRegClass) {
+    Opc = X86::MOV32mr_TC;
   } else if (RC == &X86::RFP80RegClass) {
     Opc = X86::ST_FpP80m;   // pops
   } else if (RC == &X86::RFP64RegClass) {
@@ -2131,6 +2144,10 @@
     Opc = X86::MOV16rm;
   } else if (RC == &X86::GR8_NOREXRegClass) {
     Opc = X86::MOV8rm;
+  } else if (RC == &X86::GR64_TCRegClass) {
+    Opc = X86::MOV64rm_TC;
+  } else if (RC == &X86::GR32_TCRegClass) {
+    Opc = X86::MOV32rm_TC;
   } else if (RC == &X86::RFP80RegClass) {
     Opc = X86::LD_Fp80m;
   } else if (RC == &X86::RFP64RegClass) {