[X86] Merge the different Jcc instructions for each condition code into single instructions that store the condition code as an operand.

Summary:
This avoids needing an isel pattern for each condition code. And it removes translation switches for converting between Jcc instructions and condition codes.

Now the printer, encoder and disassembler take care of converting the immediate. We use InstAliases to handle the assembly matching. But we print using the asm string in the instruction definition. The instruction itself is marked IsCodeGenOnly=1 to hide it from the assembly parser.

Reviewers: spatel, lebedev.ri, courbet, gchatelet, RKSimon

Reviewed By: RKSimon

Subscribers: MatzeB, qcolombet, eraman, hiraditya, arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60228

llvm-svn: 357802
diff --git a/llvm/lib/Target/X86/X86FastISel.cpp b/llvm/lib/Target/X86/X86FastISel.cpp
index 9edb2bf..1590cd7 100644
--- a/llvm/lib/Target/X86/X86FastISel.cpp
+++ b/llvm/lib/Target/X86/X86FastISel.cpp
@@ -1690,11 +1690,9 @@
       }
 
       bool SwapArgs;
-      unsigned BranchOpc;
       std::tie(CC, SwapArgs) = X86::getX86ConditionCode(Predicate);
       assert(CC <= X86::LAST_VALID_COND && "Unexpected condition code.");
 
-      BranchOpc = X86::GetCondBranchFromCond(CC);
       if (SwapArgs)
         std::swap(CmpLHS, CmpRHS);
 
@@ -1702,14 +1700,14 @@
       if (!X86FastEmitCompare(CmpLHS, CmpRHS, VT, CI->getDebugLoc()))
         return false;
 
-      BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(BranchOpc))
-        .addMBB(TrueMBB);
+      BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::JCC_1))
+        .addMBB(TrueMBB).addImm(CC);
 
       // X86 requires a second branch to handle UNE (and OEQ, which is mapped
       // to UNE above).
       if (NeedExtraBranch) {
-        BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::JP_1))
-          .addMBB(TrueMBB);
+        BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::JCC_1))
+          .addMBB(TrueMBB).addImm(X86::COND_P);
       }
 
       finishCondBranch(BI->getParent(), TrueMBB, FalseMBB);
@@ -1736,14 +1734,14 @@
         BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(TestOpc))
           .addReg(OpReg).addImm(1);
 
-        unsigned JmpOpc = X86::JNE_1;
+        unsigned JmpCond = X86::COND_NE;
         if (FuncInfo.MBB->isLayoutSuccessor(TrueMBB)) {
           std::swap(TrueMBB, FalseMBB);
-          JmpOpc = X86::JE_1;
+          JmpCond = X86::COND_E;
         }
 
-        BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(JmpOpc))
-          .addMBB(TrueMBB);
+        BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::JCC_1))
+          .addMBB(TrueMBB).addImm(JmpCond);
 
         finishCondBranch(BI->getParent(), TrueMBB, FalseMBB);
         return true;
@@ -1756,10 +1754,8 @@
     if (TmpReg == 0)
       return false;
 
-    unsigned BranchOpc = X86::GetCondBranchFromCond(CC);
-
-    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(BranchOpc))
-      .addMBB(TrueMBB);
+    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::JCC_1))
+      .addMBB(TrueMBB).addImm(CC);
     finishCondBranch(BI->getParent(), TrueMBB, FalseMBB);
     return true;
   }
@@ -1783,8 +1779,8 @@
   BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::TEST8ri))
       .addReg(OpReg)
       .addImm(1);
-  BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::JNE_1))
-    .addMBB(TrueMBB);
+  BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::JCC_1))
+    .addMBB(TrueMBB).addImm(X86::COND_NE);
   finishCondBranch(BI->getParent(), TrueMBB, FalseMBB);
   return true;
 }