From bba20f06de1c11f8332387788914c70bef5607df Mon Sep 17 00:00:00 2001 From: Reid Kleckner Date: Mon, 12 Jan 2015 23:28:23 +0000 Subject: musttail: Only set the inreg flag for fastcall and vectorcall Otherwise we'll attempt to forward ECX, EDX, and EAX for cdecl and stdcall thunks, leaving us with no scratch registers for indirect call targets. Fixes PR22052. llvm-svn: 225729 --- llvm/lib/CodeGen/CallingConvLower.cpp | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) (limited to 'llvm/lib/CodeGen/CallingConvLower.cpp') diff --git a/llvm/lib/CodeGen/CallingConvLower.cpp b/llvm/lib/CodeGen/CallingConvLower.cpp index fbe8b7c10e66..034ffb34b9cc 100644 --- a/llvm/lib/CodeGen/CallingConvLower.cpp +++ b/llvm/lib/CodeGen/CallingConvLower.cpp @@ -181,15 +181,28 @@ void CCState::AnalyzeCallResult(MVT VT, CCAssignFn Fn) { } } +static bool isValueTypeInRegForCC(CallingConv::ID CC, MVT VT) { + if (VT.isVector()) + return true; // Assume -msse-regparm might be in effect. + if (!VT.isInteger()) + return false; + if (CC == CallingConv::X86_VectorCall || CC == CallingConv::X86_FastCall) + return true; + return false; +} + void CCState::getRemainingRegParmsForType(SmallVectorImpl &Regs, MVT VT, CCAssignFn Fn) { unsigned SavedStackOffset = StackOffset; unsigned NumLocs = Locs.size(); - // Allocate something of this value type repeatedly with just the inreg flag - // set until we get assigned a location in memory. + // Set the 'inreg' flag if it is used for this calling convention. ISD::ArgFlagsTy Flags; - Flags.setInReg(); + if (isValueTypeInRegForCC(CallingConv, VT)) + Flags.setInReg(); + + // Allocate something of this value type repeatedly until we get assigned a + // location in memory. bool HaveRegParm = true; while (HaveRegParm) { if (Fn(0, VT, VT, CCValAssign::Full, Flags, *this)) { -- cgit v1.2.3