From 1ee37ac5d43aa88a5d1e5bfc06c5601346d16540 Mon Sep 17 00:00:00 2001
From: Dale Johannesen <dalej@apple.com>
Date: Fri, 7 May 2010 21:35:53 +0000
Subject: [PATCH] Fix PR 7087, and probably other things, by extending
 getConstantFP to accept the two supported long double target types.  This was
 not the original intent, but there are other places that assume this works
 and it's easy enough to do.

llvm-svn: 103299
---
 include/llvm/CodeGen/SelectionDAG.h       |  2 ++
 lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 12 +++++++++-
 test/CodeGen/X86/2010-05-07-ldconvert.ll  | 27 +++++++++++++++++++++++
 3 files changed, 40 insertions(+), 1 deletion(-)
 create mode 100644 test/CodeGen/X86/2010-05-07-ldconvert.ll

diff --git a/include/llvm/CodeGen/SelectionDAG.h b/include/llvm/CodeGen/SelectionDAG.h
index ae15230c961..b1af0abbad1 100644
--- a/include/llvm/CodeGen/SelectionDAG.h
+++ b/include/llvm/CodeGen/SelectionDAG.h
@@ -334,6 +334,8 @@ public:
   SDValue getTargetConstant(const ConstantInt &Val, EVT VT) {
     return getConstant(Val, VT, true);
   }
+  // The forms below that take a double should only be used for simple
+  // constants that can be exactly represented in VT.  No checks are made.
   SDValue getConstantFP(double Val, EVT VT, bool isTarget = false);
   SDValue getConstantFP(const APFloat& Val, EVT VT, bool isTarget = false);
   SDValue getConstantFP(const ConstantFP &CF, EVT VT, bool isTarget = false);
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 4854ff25f2d..e9de6d56f9a 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -964,8 +964,18 @@ SDValue SelectionDAG::getConstantFP(double Val, EVT VT, bool isTarget) {
   EVT EltVT = VT.getScalarType();
   if (EltVT==MVT::f32)
     return getConstantFP(APFloat((float)Val), VT, isTarget);
-  else
+  else if (EltVT==MVT::f64)
     return getConstantFP(APFloat(Val), VT, isTarget);
+  else if (EltVT==MVT::f80 || EltVT==MVT::f128) {
+    bool ignored;
+    APFloat apf = APFloat(Val);
+    apf.convert(*EVTToAPFloatSemantics(EltVT), APFloat::rmNearestTiesToEven,
+                &ignored);
+    return getConstantFP(apf, VT, isTarget);
+  } else {
+    assert(0 && "Unsupported type in getConstantFP");
+    return SDValue();
+  }
 }
 
 SDValue SelectionDAG::getGlobalAddress(const GlobalValue *GV,
diff --git a/test/CodeGen/X86/2010-05-07-ldconvert.ll b/test/CodeGen/X86/2010-05-07-ldconvert.ll
new file mode 100644
index 00000000000..0ba6a8fd6d7
--- /dev/null
+++ b/test/CodeGen/X86/2010-05-07-ldconvert.ll
@@ -0,0 +1,27 @@
+; RUN: llc < %s -mtriple=x86_64-apple-darwin11
+; PR 7087 - used to crash
+
+define i32 @main() ssp {
+entry:
+  %retval = alloca i32, align 4                   ; <i32*> [#uses=2]
+  %r = alloca i32, align 4                        ; <i32*> [#uses=2]
+  store i32 0, i32* %retval
+  %tmp = call x86_fp80 @llvm.powi.f80(x86_fp80 0xK3FFF8000000000000000, i32 -64) ; <x86_fp80> [#uses=1]
+  %conv = fptosi x86_fp80 %tmp to i32             ; <i32> [#uses=1]
+  store i32 %conv, i32* %r
+  %tmp1 = load i32* %r                            ; <i32> [#uses=1]
+  %tobool = icmp ne i32 %tmp1, 0                  ; <i1> [#uses=1]
+  br i1 %tobool, label %if.then, label %if.end
+
+if.then:                                          ; preds = %entry
+  call void @_Z1fv()
+  br label %if.end
+
+if.end:                                           ; preds = %if.then, %entry
+  %0 = load i32* %retval                          ; <i32> [#uses=1]
+  ret i32 %0
+}
+
+declare x86_fp80 @llvm.powi.f80(x86_fp80, i32) nounwind readonly
+
+declare void @_Z1fv()