[Hexagon] Correct update of instruction offet in HW loop fixup

llvm-svn: 328366

1 files changed, 7 insertions, 3 deletions

diff --git a/llvm/lib/Target/Hexagon/HexagonFixupHwLoops.cpp b/llvm/lib/Target/Hexagon/HexagonFixupHwLoops.cpp
index a842b672736..a6b9bcb405d 100644
--- a/llvm/lib/Target/Hexagon/HexagonFixupHwLoops.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonFixupHwLoops.cpp
@@ -20,6 +20,7 @@
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/Passes.h"
 #include "llvm/CodeGen/TargetInstrInfo.h"
+#include "llvm/Support/MathExtras.h"
 #include "llvm/PassSupport.h"
 
 using namespace llvm;
@@ -137,7 +138,7 @@ bool HexagonFixupHwLoops::fixupLoopInstrs(MachineFunction &MF) {
     MachineBasicBlock::iterator MII = MBB.begin();
     MachineBasicBlock::iterator MIE = MBB.end();
     while (MII != MIE) {
-      InstOffset += HII->getSize(*MII);
+      unsigned InstSize = HII->getSize(*MII);
       if (MII->isMetaInstruction()) {
         ++MII;
         continue;
@@ -145,8 +146,10 @@ bool HexagonFixupHwLoops::fixupLoopInstrs(MachineFunction &MF) {
       if (isHardwareLoop(*MII)) {
         assert(MII->getOperand(0).isMBB() &&
                "Expect a basic block as loop operand");
-        int diff = InstOffset - BlockToInstOffset[MII->getOperand(0).getMBB()];
-        if ((unsigned)abs(diff) > MaxLoopRange) {
+        MachineBasicBlock *TargetBB = MII->getOperand(0).getMBB();
+        unsigned Diff = AbsoluteDifference(InstOffset,
+                                           BlockToInstOffset[TargetBB]);
+        if (Diff > MaxLoopRange) {
           useExtLoopInstr(MF, MII);
           MII = MBB.erase(MII);
           Changed = true;
@@ -156,6 +159,7 @@ bool HexagonFixupHwLoops::fixupLoopInstrs(MachineFunction &MF) {
       } else {
         ++MII;
       }
+      InstOffset += InstSize;
     }
   }