[X86] Make isel select the 2-byte register form of INC/DEC even in non-64-bit mode...

[oota-llvm.git] / lib / Target / X86 / X86MCInstLower.cpp

diff --git a/lib/Target/X86/X86MCInstLower.cpp b/lib/Target/X86/X86MCInstLower.cpp
index a8330f4dd750c128dbd86700c063bca36902af82..63ccded5ac9f85f15d9ca39b0b9807bc4314bd0b 100644 (file)
--- a/lib/Target/X86/X86MCInstLower.cpp
+++ b/lib/Target/X86/X86MCInstLower.cpp
@@ -545,6 +545,24 @@ ReSimplify:
     break;
   }
 
+  case X86::DEC16r:
+  case X86::DEC32r:
+  case X86::INC16r:
+  case X86::INC32r:
+    // If we aren't in 64-bit mode we can use the 1-byte inc/dec instructions.
+    if (!AsmPrinter.getSubtarget().is64Bit()) {
+      unsigned Opcode;
+      switch (OutMI.getOpcode()) {
+      default: llvm_unreachable("Invalid opcode");
+      case X86::DEC16r: Opcode = X86::DEC16r_alt; break;
+      case X86::DEC32r: Opcode = X86::DEC32r_alt; break;
+      case X86::INC16r: Opcode = X86::INC16r_alt; break;
+      case X86::INC32r: Opcode = X86::INC32r_alt; break;
+      }
+      OutMI.setOpcode(Opcode);
+    }
+    break;
+
   // These are pseudo-ops for OR to help with the OR->ADD transformation.  We do
   // this with an ugly goto in case the resultant OR uses EAX and needs the
   // short form.
@@ -558,28 +576,6 @@ ReSimplify:
   case X86::ADD32ri8_DB:  OutMI.setOpcode(X86::OR32ri8); goto ReSimplify;
   case X86::ADD64ri8_DB:  OutMI.setOpcode(X86::OR64ri8); goto ReSimplify;
 
-  // The assembler backend wants to see branches in their small form and relax
-  // them to their large form.  The JIT can only handle the large form because
-  // it does not do relaxation.  For now, translate the large form to the
-  // small one here.
-  case X86::JMP_4: OutMI.setOpcode(X86::JMP_1); break;
-  case X86::JO_4:  OutMI.setOpcode(X86::JO_1); break;
-  case X86::JNO_4: OutMI.setOpcode(X86::JNO_1); break;
-  case X86::JB_4:  OutMI.setOpcode(X86::JB_1); break;
-  case X86::JAE_4: OutMI.setOpcode(X86::JAE_1); break;
-  case X86::JE_4:  OutMI.setOpcode(X86::JE_1); break;
-  case X86::JNE_4: OutMI.setOpcode(X86::JNE_1); break;
-  case X86::JBE_4: OutMI.setOpcode(X86::JBE_1); break;
-  case X86::JA_4:  OutMI.setOpcode(X86::JA_1); break;
-  case X86::JS_4:  OutMI.setOpcode(X86::JS_1); break;
-  case X86::JNS_4: OutMI.setOpcode(X86::JNS_1); break;
-  case X86::JP_4:  OutMI.setOpcode(X86::JP_1); break;
-  case X86::JNP_4: OutMI.setOpcode(X86::JNP_1); break;
-  case X86::JL_4:  OutMI.setOpcode(X86::JL_1); break;
-  case X86::JGE_4: OutMI.setOpcode(X86::JGE_1); break;
-  case X86::JLE_4: OutMI.setOpcode(X86::JLE_1); break;
-  case X86::JG_4:  OutMI.setOpcode(X86::JG_1); break;
-
   // Atomic load and store require a separate pseudo-inst because Acquire
   // implies mayStore and Release implies mayLoad; fix these to regular MOV
   // instructions here
@@ -624,13 +620,13 @@ ReSimplify:
   // MOV64ao8, MOV64o8a
   // XCHG16ar, XCHG32ar, XCHG64ar
   case X86::MOV8mr_NOREX:
-  case X86::MOV8mr:     SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV8ao8); break;
+  case X86::MOV8mr:     SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV8o32a); break;
   case X86::MOV8rm_NOREX:
-  case X86::MOV8rm:     SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV8o8a); break;
-  case X86::MOV16mr:    SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV16ao16); break;
-  case X86::MOV16rm:    SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV16o16a); break;
-  case X86::MOV32mr:    SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV32ao32); break;
-  case X86::MOV32rm:    SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV32o32a); break;
+  case X86::MOV8rm:     SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV8ao32); break;
+  case X86::MOV16mr:    SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV16o32a); break;
+  case X86::MOV16rm:    SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV16ao32); break;
+  case X86::MOV32mr:    SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV32o32a); break;
+  case X86::MOV32rm:    SimplifyShortMoveForm(AsmPrinter, OutMI, X86::MOV32ao32); break;
 
   case X86::ADC8ri:     SimplifyShortImmForm(OutMI, X86::ADC8i8);    break;
   case X86::ADC16ri:    SimplifyShortImmForm(OutMI, X86::ADC16i16);  break;