[llvm-commits] [llvm] r88886 - in /llvm/trunk: lib/Target/Mips/MipsISelDAGToDAG.cpp lib/Target/Mips/MipsISelLowering.cpp test/CodeGen/Mips/2009-11-16-CstPoolLoad.ll

[Bruno Cardoso Lopes]

Author: bruno
Date: Sun Nov 15 22:33:42 2009
New Revision: 88886

URL: http://llvm.org/viewvc/llvm-project?rev=88886&view=rev
Log:
- Fix a small bug while handling target constant pools (one param was missing).
- Add a smarter constant pool loading, instead of:

lui $2, %hi($CPI1_0)
addiu $2, $2, %lo($CPI1_0)
lwc1 $f0, 0($2)

Generate:

lui $2, %hi($CPI1_0)
lwc1 $f0, %lo($CPI1_0)($2)


Added:
    llvm/trunk/test/CodeGen/Mips/2009-11-16-CstPoolLoad.ll
Modified:
    llvm/trunk/lib/Target/Mips/MipsISelDAGToDAG.cpp
    llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp

Modified: llvm/trunk/lib/Target/Mips/MipsISelDAGToDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/Mips/MipsISelDAGToDAG.cpp?rev=88886&r1=88885&r2=88886&view=diff

==============================================================================
--- llvm/trunk/lib/Target/Mips/MipsISelDAGToDAG.cpp (original)
+++ llvm/trunk/lib/Target/Mips/MipsISelDAGToDAG.cpp Sun Nov 15 22:33:42 2009
@@ -170,6 +170,27 @@
         return true;
       }
     }
+
+    // When loading from constant pools, load the lower address part in
+    // the instruction itself. Instead of:
+    //  lui $2, %hi($CPI1_0)
+    //  addiu $2, $2, %lo($CPI1_0)
+    //  lwc1 $f0, 0($2)
+    // Generate:
+    //  lui $2, %hi($CPI1_0)
+    //  lwc1 $f0, %lo($CPI1_0)($2)
+    if (Addr.getOperand(0).getOpcode() == MipsISD::Hi &&
+        Addr.getOperand(1).getOpcode() == MipsISD::Lo) {
+      SDValue LoVal = Addr.getOperand(1); 
+      if (ConstantPoolSDNode *CP = dyn_cast<ConstantPoolSDNode>(
+          LoVal.getOperand(0))) {
+        if (!CP->getOffset()) {
+          Base = Addr.getOperand(0);
+          Offset = LoVal.getOperand(0);
+          return true;
+        }
+      }
+    }
   }
 
   Base   = Addr;

Modified: llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp?rev=88886&r1=88885&r2=88886&view=diff

==============================================================================
--- llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp Sun Nov 15 22:33:42 2009
@@ -568,7 +568,7 @@
   ConstantPoolSDNode *N = cast<ConstantPoolSDNode>(Op);
   Constant *C = N->getConstVal();
   SDValue CP = DAG.getTargetConstantPool(C, MVT::i32, N->getAlignment(), 
-                                         MipsII::MO_ABS_HILO);
+                                         N->getOffset(), MipsII::MO_ABS_HILO);
   // FIXME there isn't actually debug info here
   DebugLoc dl = Op.getDebugLoc();
 

Added: llvm/trunk/test/CodeGen/Mips/2009-11-16-CstPoolLoad.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Mips/2009-11-16-CstPoolLoad.ll?rev=88886&view=auto

==============================================================================
--- llvm/trunk/test/CodeGen/Mips/2009-11-16-CstPoolLoad.ll (added)
+++ llvm/trunk/test/CodeGen/Mips/2009-11-16-CstPoolLoad.ll Sun Nov 15 22:33:42 2009
@@ -0,0 +1,10 @@
+; RUN: llc < %s | FileCheck %s
+target datalayout = "E-p:32:32:32-i1:8:8-i8:8:32-i16:16:32-i32:32:32-i64:32:64-f32:32:32-f64:64:64-v64:64:64-n32"
+target triple = "mips-unknown-linux"
+
+define float @h() nounwind readnone {
+entry:
+; CHECK: lui $2, %hi($CPI1_0)
+; CHECK: lwc1 $f0, %lo($CPI1_0)($2)
+  ret float 0x400B333340000000
+}