Fix darwin ppc llvm-gcc build breakage: intercept

ppcf128 to i32 conversion and expand it into a code
sequence like in LegalizeDAG.  This needs custom
ppc lowering of FP_ROUND_INREG, so turn that on and
make it work with LegalizeTypes.  Probably PPC should
simply custom lower the original conversion.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@58329 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 75 insertions, 5 deletions

diff --git a/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp
index f134388..c3b2d40 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp
@@ -902,6 +902,18 @@ SDValue DAGTypeLegalizer::ExpandFloatOp_FP_ROUND(SDNode *N) {
 
 SDValue DAGTypeLegalizer::ExpandFloatOp_FP_TO_SINT(SDNode *N) {
   MVT RVT = N->getValueType(0);
+
+  // Expand ppcf128 to i32 by hand for the benefit of llvm-gcc bootstrap on
+  // PPC (the libcall is not available).  FIXME: Do this in a less hacky way.
+  if (RVT == MVT::i32) {
+    assert(N->getOperand(0).getValueType() == MVT::ppcf128 &&
+           "Logic only correct for ppcf128!");
+    SDValue Res = DAG.getNode(ISD::FP_ROUND_INREG, MVT::ppcf128,
+                              N->getOperand(0), DAG.getValueType(MVT::f64));
+    Res = DAG.getNode(ISD::FP_ROUND, MVT::f64, Res, DAG.getIntPtrConstant(1));
+    return DAG.getNode(ISD::FP_TO_SINT, MVT::i32, Res);
+  }
+
   RTLIB::Libcall LC = RTLIB::getFPTOSINT(N->getOperand(0).getValueType(), RVT);
   assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unsupported FP_TO_SINT!");
   return MakeLibCall(LC, RVT, &N->getOperand(0), 1, false);
@@ -909,6 +921,29 @@ SDValue DAGTypeLegalizer::ExpandFloatOp_FP_TO_SINT(SDNode *N) {
 
 SDValue DAGTypeLegalizer::ExpandFloatOp_FP_TO_UINT(SDNode *N) {
   MVT RVT = N->getValueType(0);
+
+  // Expand ppcf128 to i32 by hand for the benefit of llvm-gcc bootstrap on
+  // PPC (the libcall is not available).  FIXME: Do this in a less hacky way.
+  if (RVT == MVT::i32) {
+    assert(N->getOperand(0).getValueType() == MVT::ppcf128 &&
+           "Logic only correct for ppcf128!");
+    const uint64_t TwoE31[] = {0x41e0000000000000LL, 0};
+    APFloat APF = APFloat(APInt(128, 2, TwoE31));
+    SDValue Tmp = DAG.getConstantFP(APF, MVT::ppcf128);
+    //  X>=2^31 ? (int)(X-2^31)+0x80000000 : (int)X
+    // FIXME: generated code sucks.
+    return DAG.getNode(ISD::SELECT_CC, MVT::i32, N->getOperand(0), Tmp,
+                       DAG.getNode(ISD::ADD, MVT::i32,
+                                   DAG.getNode(ISD::FP_TO_SINT, MVT::i32,
+                                               DAG.getNode(ISD::FSUB,
+                                                           MVT::ppcf128,
+                                                           N->getOperand(0),
+                                                           Tmp)),
+                                   DAG.getConstant(0x80000000, MVT::i32)),
+                       DAG.getNode(ISD::FP_TO_SINT, MVT::i32, N->getOperand(0)),
+                       DAG.getCondCode(ISD::SETGE));
+  }
+
   RTLIB::Libcall LC = RTLIB::getFPTOUINT(N->getOperand(0).getValueType(), RVT);
   assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unsupported FP_TO_UINT!");
   return MakeLibCall(LC, N->getValueType(0), &N->getOperand(0), 1, false);
diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index eb327dc..5cf7eb2 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -2865,9 +2865,10 @@ SDValue PPCTargetLowering::LowerFP_ROUND_INREG(SDValue Op,
   assert(Op.getValueType() == MVT::ppcf128);
   SDNode *Node = Op.getNode();
   assert(Node->getOperand(0).getValueType() == MVT::ppcf128);
-  assert(Node->getOperand(0).getNode()->getOpcode() == ISD::BUILD_PAIR);
-  SDValue Lo = Node->getOperand(0).getNode()->getOperand(0);
-  SDValue Hi = Node->getOperand(0).getNode()->getOperand(1);
+  SDValue Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, MVT::f64, Node->getOperand(0),
+                           DAG.getIntPtrConstant(0));
+  SDValue Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, MVT::f64, Node->getOperand(0),
+                           DAG.getIntPtrConstant(1));
 
   // This sequence changes FPSCR to do round-to-zero, adds the two halves
   // of the long double, and puts FPSCR back the way it was.  We do not
@@ -2916,7 +2917,7 @@ SDValue PPCTargetLowering::LowerFP_ROUND_INREG(SDValue Op,
 
   // We know the low half is about to be thrown away, so just use something
   // convenient.
-  return DAG.getNode(ISD::BUILD_PAIR, Lo.getValueType(), FPreg, FPreg);
+  return DAG.getNode(ISD::BUILD_PAIR, MVT::ppcf128, FPreg, FPreg);
 }
 
 SDValue PPCTargetLowering::LowerSINT_TO_FP(SDValue Op, SelectionDAG &DAG) {
@@ -3883,7 +3884,8 @@ SDValue PPCTargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) {
 
 SDNode *PPCTargetLowering::ReplaceNodeResults(SDNode *N, SelectionDAG &DAG) {
   switch (N->getOpcode()) {
-  default: assert(0 && "Wasn't expecting to be able to lower this!");
+  default:
+    return PPCTargetLowering::LowerOperation(SDValue (N, 0), DAG).getNode();
   case ISD::FP_TO_SINT: {
     SDValue Res = LowerFP_TO_SINT(SDValue(N, 0), DAG);
     // Use MERGE_VALUES to drop the chain result value and get a node with one
diff --git a/test/CodeGen/PowerPC/2008-10-28-f128-i32.ll b/test/CodeGen/PowerPC/2008-10-28-f128-i32.ll
new file mode 100644
index 0000000..4db5773
--- /dev/null
+++ b/test/CodeGen/PowerPC/2008-10-28-f128-i32.ll
@@ -0,0 +1,33 @@
+; RUN: llvm-as < %s | llc -march=ppc32 -o - | not grep fixunstfsi
+
+define i64 @__fixunstfdi(ppc_fp128 %a) nounwind readnone {
+entry:
+	%0 = fcmp olt ppc_fp128 %a, 0xM00000000000000000000000000000000		; <i1> [#uses=1]
+	br i1 %0, label %bb5, label %bb1
+
+bb1:		; preds = %entry
+	%1 = mul ppc_fp128 %a, 0xM3DF00000000000000000000000000000		; <ppc_fp128> [#uses=1]
+	%2 = fptoui ppc_fp128 %1 to i32		; <i32> [#uses=1]
+	%3 = zext i32 %2 to i64		; <i64> [#uses=1]
+	%4 = shl i64 %3, 32		; <i64> [#uses=3]
+	%5 = uitofp i64 %4 to ppc_fp128		; <ppc_fp128> [#uses=1]
+	%6 = sub ppc_fp128 %a, %5		; <ppc_fp128> [#uses=3]
+	%7 = fcmp olt ppc_fp128 %6, 0xM00000000000000000000000000000000		; <i1> [#uses=1]
+	br i1 %7, label %bb2, label %bb3
+
+bb2:		; preds = %bb1
+	%8 = sub ppc_fp128 0xM80000000000000000000000000000000, %6		; <ppc_fp128> [#uses=1]
+	%9 = fptoui ppc_fp128 %8 to i32		; <i32> [#uses=1]
+	%10 = zext i32 %9 to i64		; <i64> [#uses=1]
+	%11 = sub i64 %4, %10		; <i64> [#uses=1]
+	ret i64 %11
+
+bb3:		; preds = %bb1
+	%12 = fptoui ppc_fp128 %6 to i32		; <i32> [#uses=1]
+	%13 = zext i32 %12 to i64		; <i64> [#uses=1]
+	%14 = or i64 %13, %4		; <i64> [#uses=1]
+	ret i64 %14
+
+bb5:		; preds = %entry
+	ret i64 0
+}