[llvm-commits] [llvm] r63323 - in /llvm/trunk: lib/CodeGen/RegAllocLocal.cpp test/CodeGen/X86/2009-01-29-LocalRegAllocBug.ll

[Evan Cheng]

Author: evancheng
Date: Thu Jan 29 12:37:30 2009
New Revision: 63323

URL: http://llvm.org/viewvc/llvm-project?rev=63323&view=rev
Log:
Local register allocator shouldn't assume only the entry and landing pad basic blocks have live-ins.

Added:
    llvm/trunk/test/CodeGen/X86/2009-01-29-LocalRegAllocBug.ll
Modified:
    llvm/trunk/lib/CodeGen/RegAllocLocal.cpp

Modified: llvm/trunk/lib/CodeGen/RegAllocLocal.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/RegAllocLocal.cpp?rev=63323&r1=63322&r2=63323&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/RegAllocLocal.cpp (original)
+++ llvm/trunk/lib/CodeGen/RegAllocLocal.cpp Thu Jan 29 12:37:30 2009
@@ -710,24 +710,21 @@
   DEBUG(const BasicBlock *LBB = MBB.getBasicBlock();
         if (LBB) DOUT << "\nStarting RegAlloc of BB: " << LBB->getName());
 
-  // If this is the first basic block in the machine function, add live-in
-  // registers as active.
-  if (&MBB == &*MF->begin() || MBB.isLandingPad()) {
-    for (MachineBasicBlock::livein_iterator I = MBB.livein_begin(),
+  // Add live-in registers as active.
+  for (MachineBasicBlock::livein_iterator I = MBB.livein_begin(),
          E = MBB.livein_end(); I != E; ++I) {
-      unsigned Reg = *I;
-      MF->getRegInfo().setPhysRegUsed(Reg);
-      PhysRegsUsed[Reg] = 0;            // It is free and reserved now
-      AddToPhysRegsUseOrder(Reg); 
-      for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
-           *SubRegs; ++SubRegs) {
-        if (PhysRegsUsed[*SubRegs] != -2) {
-          AddToPhysRegsUseOrder(*SubRegs); 
-          PhysRegsUsed[*SubRegs] = 0;  // It is free and reserved now
-          MF->getRegInfo().setPhysRegUsed(*SubRegs);
-        }
+    unsigned Reg = *I;
+    MF->getRegInfo().setPhysRegUsed(Reg);
+    PhysRegsUsed[Reg] = 0;            // It is free and reserved now
+    AddToPhysRegsUseOrder(Reg); 
+    for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
+         *SubRegs; ++SubRegs) {
+      if (PhysRegsUsed[*SubRegs] != -2) {
+        AddToPhysRegsUseOrder(*SubRegs); 
+        PhysRegsUsed[*SubRegs] = 0;  // It is free and reserved now
+        MF->getRegInfo().setPhysRegUsed(*SubRegs);
       }
-    }    
+    }
   }
   
   ComputeLocalLiveness(MBB);

Added: llvm/trunk/test/CodeGen/X86/2009-01-29-LocalRegAllocBug.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/2009-01-29-LocalRegAllocBug.ll?rev=63323&view=auto

==============================================================================
--- llvm/trunk/test/CodeGen/X86/2009-01-29-LocalRegAllocBug.ll (added)
+++ llvm/trunk/test/CodeGen/X86/2009-01-29-LocalRegAllocBug.ll Thu Jan 29 12:37:30 2009
@@ -0,0 +1,38 @@
+; RUN: llvm-as < %s | llc -mtriple=i386-apple-darwin9.6 -regalloc=local -disable-fp-elim
+; rdar://6538384
+
+	%struct.FILE = type { i8*, i32, i32, i16, i16, %struct.__sbuf, i32, i8*, i32 (i8*)*, i32 (i8*, i8*, i32)*, i64 (i8*, i64, i32)*, i32 (i8*, i8*, i32)*, %struct.__sbuf, %struct.__sFILEX*, i32, [3 x i8], [1 x i8], %struct.__sbuf, i32, i64 }
+	%struct.Lit = type { i32 }
+	%struct.StreamBuffer = type { %struct.FILE*, [1048576 x i8], i32, i32 }
+	%struct.__sFILEX = type opaque
+	%struct.__sbuf = type { i8*, i32 }
+
+declare fastcc i32 @_Z8parseIntI12StreamBufferEiRT_(%struct.StreamBuffer*)
+
+declare i8* @llvm.eh.exception() nounwind
+
+define i32 @main(i32 %argc, i8** nocapture %argv) noreturn {
+entry:
+	%0 = invoke fastcc i32 @_Z8parseIntI12StreamBufferEiRT_(%struct.StreamBuffer* null)
+			to label %bb1.i16.i.i unwind label %lpad.i.i		; <i32> [#uses=0]
+
+bb1.i16.i.i:		; preds = %entry
+	br i1 false, label %bb.i.i.i.i, label %_ZN3vecI3LitE4pushERKS0_.exit.i.i.i
+
+bb.i.i.i.i:		; preds = %bb1.i16.i.i
+	br label %_ZN3vecI3LitE4pushERKS0_.exit.i.i.i
+
+_ZN3vecI3LitE4pushERKS0_.exit.i.i.i:		; preds = %bb.i.i.i.i, %bb1.i16.i.i
+	%lits.i.i.0.0 = phi %struct.Lit* [ null, %bb1.i16.i.i ], [ null, %bb.i.i.i.i ]		; <%struct.Lit*> [#uses=1]
+	%1 = invoke fastcc i32 @_Z8parseIntI12StreamBufferEiRT_(%struct.StreamBuffer* null)
+			to label %.noexc21.i.i unwind label %lpad.i.i		; <i32> [#uses=0]
+
+.noexc21.i.i:		; preds = %_ZN3vecI3LitE4pushERKS0_.exit.i.i.i
+	unreachable
+
+lpad.i.i:		; preds = %_ZN3vecI3LitE4pushERKS0_.exit.i.i.i, %entry
+	%lits.i.i.0.3 = phi %struct.Lit* [ %lits.i.i.0.0, %_ZN3vecI3LitE4pushERKS0_.exit.i.i.i ], [ null, %entry ]		; <%struct.Lit*> [#uses=1]
+	%eh_ptr.i.i = call i8* @llvm.eh.exception()		; <i8*> [#uses=0]
+	free %struct.Lit* %lits.i.i.0.3
+	unreachable
+}