From f91abd22be9c98abcba50952cfcd39d5264417b6 Mon Sep 17 00:00:00 2001
From: Eli Friedman <eli.friedman@gmail.com>
Date: Wed, 7 Dec 2011 00:50:54 +0000
Subject: [PATCH] Support vector bitcasts in the AsmPrinter.  PR11495.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146001 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/AsmPrinter/AsmPrinter.cpp         | 26 +++++++++++++++++--
 .../X86/2011-12-06-BitcastVectorGlobal.ll     |  5 ++++
 2 files changed, 29 insertions(+), 2 deletions(-)
 create mode 100644 test/CodeGen/X86/2011-12-06-BitcastVectorGlobal.ll

diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 8c69a3aca81..23bf602bade 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -1642,6 +1642,28 @@ static void EmitGlobalConstantVector(const ConstantVector *CV,
     AP.OutStreamer.EmitZeros(Padding, AddrSpace);
 }
 
+static void LowerVectorConstant(const Constant *CV, unsigned AddrSpace,
+                                AsmPrinter &AP) {
+  // Look through bitcasts
+  if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV))
+    if (CE->getOpcode() == Instruction::BitCast)
+      CV = CE->getOperand(0);
+
+  if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
+    return EmitGlobalConstantVector(V, AddrSpace, AP);
+
+  // If we get here, we're stuck; report the problem to the user.
+  // FIXME: Are there any other useful tricks for vectors?
+  {
+    std::string S;
+    raw_string_ostream OS(S);
+    OS << "Unsupported vector expression in static initializer: ";
+    WriteAsOperand(OS, CV, /*PrintType=*/false,
+                   !AP.MF ? 0 : AP.MF->getFunction()->getParent());
+    report_fatal_error(OS.str());
+  }
+}
+
 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
                                      unsigned AddrSpace, AsmPrinter &AP) {
   // Print the fields in successive locations. Pad to align if needed!
@@ -1796,8 +1818,8 @@ static void EmitGlobalConstantImpl(const Constant *CV, unsigned AddrSpace,
     return;
   }
 
-  if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
-    return EmitGlobalConstantVector(V, AddrSpace, AP);
+  if (CV->getType()->isVectorTy())
+    return LowerVectorConstant(CV, AddrSpace, AP);
 
   // Otherwise, it must be a ConstantExpr.  Lower it to an MCExpr, then emit it
   // thread the streamer with EmitValue.
diff --git a/test/CodeGen/X86/2011-12-06-BitcastVectorGlobal.ll b/test/CodeGen/X86/2011-12-06-BitcastVectorGlobal.ll
new file mode 100644
index 00000000000..7a4126f4ae2
--- /dev/null
+++ b/test/CodeGen/X86/2011-12-06-BitcastVectorGlobal.ll
@@ -0,0 +1,5 @@
+; RUN: llc < %s -march=x86-64 | FileCheck %s
+; PR11495
+
+; CHECK: 1311768467463790320
+@v = global <2 x float> bitcast (<1 x i64> <i64 1311768467463790320> to <2 x float>), align 8