Fix i64->f64 conversion, x86-64, -no-sse. A bit

tricky since there's a 3rd 64-bit type, MMX vectors.
PR 7135.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104308 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 45 insertions, 0 deletions

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 4206cbb2ee..78144abe80 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -217,6 +217,11 @@ X86TargetLowering::X86TargetLowering(X86TargetMachine &TM)
   if (!X86ScalarSSEf64) {
     setOperationAction(ISD::BIT_CONVERT      , MVT::f32  , Expand);
     setOperationAction(ISD::BIT_CONVERT      , MVT::i32  , Expand);
+    if (Subtarget->is64Bit() && Subtarget->hasMMX() && !DisableMMX) {
+      // Without SSE, i64->f64 goes through memory; i64->MMX is legal.
+      setOperationAction(ISD::BIT_CONVERT    , MVT::i64  , Custom);
+      setOperationAction(ISD::BIT_CONVERT    , MVT::f64  , Expand);
+    }
   }
 
   // Scalar integer divide and remainder are lowered to use operations that
@@ -678,6 +683,14 @@ X86TargetLowering::X86TargetLowering(X86TargetMachine &TM)
     setOperationAction(ISD::VSETCC,             MVT::v8i8, Custom);
     setOperationAction(ISD::VSETCC,             MVT::v4i16, Custom);
     setOperationAction(ISD::VSETCC,             MVT::v2i32, Custom);
+
+    if (!X86ScalarSSEf64 && Subtarget->is64Bit()) {
+      setOperationAction(ISD::BIT_CONVERT,        MVT::v8i8,  Custom);
+      setOperationAction(ISD::BIT_CONVERT,        MVT::v4i16, Custom);
+      setOperationAction(ISD::BIT_CONVERT,        MVT::v2i32, Custom);
+      setOperationAction(ISD::BIT_CONVERT,        MVT::v2f32, Custom);
+      setOperationAction(ISD::BIT_CONVERT,        MVT::v1i64, Custom);
+    }
   }
 
   if (!UseSoftFloat && Subtarget->hasSSE1()) {
@@ -7458,6 +7471,24 @@ SDValue X86TargetLowering::LowerREADCYCLECOUNTER(SDValue Op,
   return DAG.getMergeValues(Ops, 2, dl);
 }
 
+SDValue X86TargetLowering::LowerBIT_CONVERT(SDValue Op,
+                                            SelectionDAG &DAG) const {
+  EVT SrcVT = Op.getOperand(0).getValueType();
+  EVT DstVT = Op.getValueType();
+  assert((Subtarget->is64Bit() && !Subtarget->hasSSE2() && 
+          Subtarget->hasMMX() && !DisableMMX) &&
+         "Unexpected custom BIT_CONVERT");
+  assert((DstVT == MVT::i64 || 
+          (DstVT.isVector() && DstVT.getSizeInBits()==64)) &&
+         "Unexpected custom BIT_CONVERT");
+  // i64 <=> MMX conversions are Legal.
+  if (SrcVT==MVT::i64 && DstVT.isVector())
+    return Op;
+  if (DstVT==MVT::i64 && SrcVT.isVector())
+    return Op;
+  // All other conversions need to be expanded.
+  return SDValue();
+}
 SDValue X86TargetLowering::LowerLOAD_SUB(SDValue Op, SelectionDAG &DAG) const {
   SDNode *Node = Op.getNode();
   DebugLoc dl = Node->getDebugLoc();
@@ -7527,6 +7558,7 @@ SDValue X86TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
   case ISD::SMULO:
   case ISD::UMULO:              return LowerXALUO(Op, DAG);
   case ISD::READCYCLECOUNTER:   return LowerREADCYCLECOUNTER(Op, DAG);
+  case ISD::BIT_CONVERT:        return LowerBIT_CONVERT(Op, DAG);
   }
 }
 
diff --git a/lib/Target/X86/X86ISelLowering.h b/lib/Target/X86/X86ISelLowering.h
index 06491bf57e..1ef1a7b018 100644
--- a/lib/Target/X86/X86ISelLowering.h
+++ b/lib/Target/X86/X86ISelLowering.h
@@ -677,6 +677,7 @@ namespace llvm {
     SDValue LowerShift(SDValue Op, SelectionDAG &DAG) const;
     SDValue BuildFILD(SDValue Op, EVT SrcVT, SDValue Chain, SDValue StackSlot,
                       SelectionDAG &DAG) const;
+    SDValue LowerBIT_CONVERT(SDValue op, SelectionDAG &DAG) const;
     SDValue LowerSINT_TO_FP(SDValue Op, SelectionDAG &DAG) const;
     SDValue LowerUINT_TO_FP(SDValue Op, SelectionDAG &DAG) const;
     SDValue LowerUINT_TO_FP_i64(SDValue Op, SelectionDAG &DAG) const;
diff --git a/test/CodeGen/X86/2010-05-16-nosseconversion.ll b/test/CodeGen/X86/2010-05-16-nosseconversion.ll
new file mode 100644
index 0000000000..889575cea3
--- /dev/null
+++ b/test/CodeGen/X86/2010-05-16-nosseconversion.ll
@@ -0,0 +1,12 @@
+; RUN: llc -mtriple=x86_64-apple-darwin -mattr=-sse < %s
+; PR 7135
+
+@x = common global i64 0                          ; <i64*> [#uses=1]
+
+define i32 @foo() nounwind readonly ssp {
+entry:
+  %0 = load i64* @x, align 8                      ; <i64> [#uses=1]
+  %1 = uitofp i64 %0 to double                    ; <double> [#uses=1]
+  %2 = fptosi double %1 to i32                    ; <i32> [#uses=1]
+  ret i32 %2
+}