Infrastructure for getting the machine code size of a function and an instruction. X86, PowerPC and ARM are implemented

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49809 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 26 insertions, 22 deletions

diff --git a/lib/Target/PowerPC/PPCBranchSelector.cpp b/lib/Target/PowerPC/PPCBranchSelector.cpp
index 6977093..ab988ba 100644
--- a/lib/Target/PowerPC/PPCBranchSelector.cpp
+++ b/lib/Target/PowerPC/PPCBranchSelector.cpp
@@ -22,7 +22,6 @@
 #include "PPCPredicates.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetAsmInfo.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/MathExtras.h"
@@ -54,25 +53,6 @@ FunctionPass *llvm::createPPCBranchSelectionPass() {
   return new PPCBSel();
 }
 
-/// getNumBytesForInstruction - Return the number of bytes of code the specified
-/// instruction may be.  This returns the maximum number of bytes.
-///
-static unsigned getNumBytesForInstruction(MachineInstr *MI) {
-  switch (MI->getOpcode()) {
-  case PPC::INLINEASM: {       // Inline Asm: Variable size.
-    MachineFunction *MF = MI->getParent()->getParent();
-    const char *AsmStr = MI->getOperand(0).getSymbolName();
-    return MF->getTarget().getTargetAsmInfo()->getInlineAsmLength(AsmStr);
-  }
-  case PPC::LABEL: {
-    return 0;
-  }
-  default:
-    return 4; // PowerPC instructions are all 4 bytes
-  }
-}
-
-
 bool PPCBSel::runOnMachineFunction(MachineFunction &Fn) {
   const TargetInstrInfo *TII = Fn.getTarget().getInstrInfo();
   // Give the blocks of the function a dense, in-order, numbering.
@@ -88,7 +68,7 @@ bool PPCBSel::runOnMachineFunction(MachineFunction &Fn) {
     unsigned BlockSize = 0;
     for (MachineBasicBlock::iterator MBBI = MBB->begin(), EE = MBB->end();
          MBBI != EE; ++MBBI)
-      BlockSize += getNumBytesForInstruction(MBBI);
+      BlockSize += TII->GetInstSizeInBytes(MBBI);
     
     BlockSizes[MBB->getNumber()] = BlockSize;
     FuncSize += BlockSize;
@@ -124,7 +104,7 @@ bool PPCBSel::runOnMachineFunction(MachineFunction &Fn) {
       for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end();
            I != E; ++I) {
         if (I->getOpcode() != PPC::BCC || I->getOperand(2).isImmediate()) {
-          MBBStartOffset += getNumBytesForInstruction(I);
+          MBBStartOffset += TII->GetInstSizeInBytes(I);
           continue;
         }
         
diff --git a/lib/Target/PowerPC/PPCInstrInfo.cpp b/lib/Target/PowerPC/PPCInstrInfo.cpp
index ff7d42e..27ff767 100644
--- a/lib/Target/PowerPC/PPCInstrInfo.cpp
+++ b/lib/Target/PowerPC/PPCInstrInfo.cpp
@@ -20,6 +20,7 @@
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/Support/CommandLine.h"
+#include "llvm/Target/TargetAsmInfo.h"
 using namespace llvm;
 
 extern cl::opt<bool> EnablePPC32RS;  // FIXME (64-bit): See PPCRegisterInfo.cpp.
@@ -724,3 +725,21 @@ ReverseBranchCondition(std::vector<MachineOperand> &Cond) const {
   Cond[0].setImm(PPC::InvertPredicate((PPC::Predicate)Cond[0].getImm()));
   return false;
 }
+
+/// GetInstSize - Return the number of bytes of code the specified
+/// instruction may be.  This returns the maximum number of bytes.
+///
+unsigned PPCInstrInfo::GetInstSizeInBytes(const MachineInstr *MI) const {
+  switch (MI->getOpcode()) {
+  case PPC::INLINEASM: {       // Inline Asm: Variable size.
+    const MachineFunction *MF = MI->getParent()->getParent();
+    const char *AsmStr = MI->getOperand(0).getSymbolName();
+    return MF->getTarget().getTargetAsmInfo()->getInlineAsmLength(AsmStr);
+  }
+  case PPC::LABEL: {
+    return 0;
+  }
+  default:
+    return 4; // PowerPC instructions are all 4 bytes
+  }
+}
diff --git a/lib/Target/PowerPC/PPCInstrInfo.h b/lib/Target/PowerPC/PPCInstrInfo.h
index d74399d..5bd4c4d 100644
--- a/lib/Target/PowerPC/PPCInstrInfo.h
+++ b/lib/Target/PowerPC/PPCInstrInfo.h
@@ -155,6 +155,11 @@ public:
   
   virtual bool BlockHasNoFallThrough(MachineBasicBlock &MBB) const;
   virtual bool ReverseBranchCondition(std::vector<MachineOperand> &Cond) const;
+  
+  /// GetInstSize - Return the number of bytes of code the specified
+  /// instruction may be.  This returns the maximum number of bytes.
+  ///
+  virtual unsigned GetInstSizeInBytes(const MachineInstr *MI) const;
 };
 
 }