[llvm] r194309 - [mips] Make sure there is a chain edge dependency between loads that read

[Akira Hatanaka]

Author: ahatanak
Date: Fri Nov  8 20:38:51 2013
New Revision: 194309

URL: http://llvm.org/viewvc/llvm-project?rev=194309&view=rev
Log:
[mips] Make sure there is a chain edge dependency between loads that read
formal arguments on the stack and stores created afterwards. We need this to
ensure tail call optimized function calls do not write over the argument area
of the stack before it is read out.
 

Modified:
    llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp
    llvm/trunk/test/CodeGen/Mips/i64arg.ll
    llvm/trunk/test/CodeGen/Mips/tailcall.ll

Modified: llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp?rev=194309&r1=194308&r2=194309&view=diff
==============================================================================
--- llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp Fri Nov  8 20:38:51 2013
@@ -2650,9 +2650,11 @@ MipsTargetLowering::LowerFormalArguments
 
       // Create load nodes to retrieve arguments from the stack
       SDValue FIN = DAG.getFrameIndex(FI, getPointerTy());
-      InVals.push_back(DAG.getLoad(ValVT, DL, Chain, FIN,
-                                   MachinePointerInfo::getFixedStack(FI),
-                                   false, false, false, 0));
+      SDValue Load = DAG.getLoad(ValVT, DL, Chain, FIN,
+                                 MachinePointerInfo::getFixedStack(FI),
+                                 false, false, false, 0);
+      InVals.push_back(Load);
+      OutChains.push_back(Load.getValue(1));
     }
   }
 

Modified: llvm/trunk/test/CodeGen/Mips/i64arg.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Mips/i64arg.ll?rev=194309&r1=194308&r2=194309&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/Mips/i64arg.ll (original)
+++ llvm/trunk/test/CodeGen/Mips/i64arg.ll Fri Nov  8 20:38:51 2013
@@ -2,16 +2,16 @@
 
 define void @f1(i64 %ll1, float %f, i64 %ll, i32 %i, float %f2) nounwind {
 entry:
-; CHECK: move $[[R1:[0-9]+]], $5
-; CHECK: move $[[R0:[0-9]+]], $4
-; CHECK: ori $6, ${{[0-9]+}}, 3855
-; CHECK: ori $7, ${{[0-9]+}}, 22136
-; CHECK: lw  $25, %call16(ff1)
+; CHECK-DAG: lw $[[R2:[0-9]+]], 80($sp)
+; CHECK-DAG: lw $[[R3:[0-9]+]], 84($sp)
+; CHECK-DAG: move $[[R1:[0-9]+]], $5
+; CHECK-DAG: move $[[R0:[0-9]+]], $4
+; CHECK-DAG: ori $6, ${{[0-9]+}}, 3855
+; CHECK-DAG: ori $7, ${{[0-9]+}}, 22136
+; CHECK-DAG: lw  $25, %call16(ff1)
 ; CHECK: jalr
   tail call void @ff1(i32 %i, i64 1085102592623924856) nounwind
 ; CHECK-DAG: lw $25, %call16(ff2)
-; CHECK-DAG: lw $[[R2:[0-9]+]], 80($sp)
-; CHECK-DAG: lw $[[R3:[0-9]+]], 84($sp)
 ; CHECK-DAG: move $4, $[[R2]]
 ; CHECK-DAG: move $5, $[[R3]]
 ; CHECK: jalr $25

Modified: llvm/trunk/test/CodeGen/Mips/tailcall.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Mips/tailcall.ll?rev=194309&r1=194308&r2=194309&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/Mips/tailcall.ll (original)
+++ llvm/trunk/test/CodeGen/Mips/tailcall.ll Fri Nov  8 20:38:51 2013
@@ -243,3 +243,16 @@ entry:
   ret i32 %call
 }
 
+; Check that there is a chain edge between the load and store nodes.
+;
+; PIC32-LABEL: caller14:
+; PIC32: lw ${{[0-9]+}}, 16($sp)
+; PIC32: sw $4, 16($sp)
+
+define void @caller14(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) {
+entry:
+  tail call void @callee14(i32 %e, i32 %b, i32 %c, i32 %d, i32 %a)
+  ret void
+}
+
+declare void @callee14(i32, i32, i32, i32, i32)