Inspired by seeing "MIPS" go by in the commits, I've gone ahead and
implemented a (codegen) target hook for __builtin_extend_pointer.
I'm also making it return a uint64_t instead of an unsigned word; this
comports with typical usage (i.e. the one use I know of).
I don't know if any of the existing targets requires this hook to be
set (other than x86 and x86_64, which I know do not).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@97547 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGBuiltin.cpp b/lib/CodeGen/CGBuiltin.cpp
index 1956abf..0c875f7 100644
--- a/lib/CodeGen/CGBuiltin.cpp
+++ b/lib/CodeGen/CGBuiltin.cpp
@@ -11,6 +11,7 @@
//
//===----------------------------------------------------------------------===//
+#include "TargetInfo.h"
#include "CodeGenFunction.h"
#include "CodeGenModule.h"
#include "clang/Basic/TargetInfo.h"
@@ -19,6 +20,7 @@
#include "clang/AST/Decl.h"
#include "clang/Basic/TargetBuiltins.h"
#include "llvm/Intrinsics.h"
+#include "llvm/Target/TargetData.h"
using namespace clang;
using namespace CodeGen;
using namespace llvm;
@@ -367,19 +369,32 @@
}
case Builtin::BI__builtin_extend_pointer: {
// Extends a pointer to the size of an _Unwind_Word, which is
- // generally a uint64_t. Generally this gets poked directly into
- // a register (or a "register" depending on platform) and then
- // called, so if the pointer is shorter than a word we need to
- // zext / sext based on the platform's expectations for pointers
- // in registers.
+ // uint64_t on all platforms. Generally this gets poked into a
+ // register and eventually used as an address, so if the
+ // addressing registers are wider than pointers and the platform
+ // doesn't implicitly ignore high-order bits when doing
+ // addressing, we need to make sure we zext / sext based on
+ // the platform's expectations.
//
// See: http://gcc.gnu.org/ml/gcc-bugs/2002-02/msg00237.html
- //
- // FIXME: ptrtoint always zexts; use a target hook if we start
- // supporting targets where this matters.
+
+ LLVMContext &C = CGM.getLLVMContext();
+
+ // Cast the pointer to intptr_t.
Value *Ptr = EmitScalarExpr(E->getArg(0));
- const llvm::Type *Ty = CGM.getTypes().ConvertType(E->getType());
- return RValue::get(Builder.CreatePtrToInt(Ptr, Ty));
+ const llvm::IntegerType *IntPtrTy = CGM.getTargetData().getIntPtrType(C);
+ Value *Result = Builder.CreatePtrToInt(Ptr, IntPtrTy, "extend.cast");
+
+ // If that's 64 bits, we're done.
+ if (IntPtrTy->getBitWidth() == 64)
+ return RValue::get(Result);
+
+ // Otherwise, ask the codegen data what to do.
+ const llvm::IntegerType *Int64Ty = llvm::IntegerType::get(C, 64);
+ if (CGM.getTargetCodeGenInfo().extendPointerWithSExt())
+ return RValue::get(Builder.CreateSExt(Result, Int64Ty, "extend.sext"));
+ else
+ return RValue::get(Builder.CreateZExt(Result, Int64Ty, "extend.zext"));
}
#if 0
// FIXME: Finish/enable when LLVM backend support stabilizes