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author | Reid Kleckner <reid@kleckner.net> | 2014-01-31 17:41:22 +0000 |
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committer | Reid Kleckner <reid@kleckner.net> | 2014-01-31 17:41:22 +0000 |
commit | 65c98b9da474d0562f883d6001f31ba5b2b95183 (patch) | |
tree | 18a2b8a062180aa9b4f289b5caa8db5e1d7aa061 | |
parent | 0cb94d9adc631eafa88218a5e972d45e0cf35f61 (diff) | |
download | llvm-65c98b9da474d0562f883d6001f31ba5b2b95183.tar.gz llvm-65c98b9da474d0562f883d6001f31ba5b2b95183.tar.bz2 llvm-65c98b9da474d0562f883d6001f31ba5b2b95183.tar.xz |
[ms-cxxabi] Add a new calling convention that swaps 'this' and 'sret'
MSVC always places the 'this' parameter for a method first. The
implicit 'sret' pointer for methods always comes second. We already
implement this for __thiscall by putting sret parameters on the stack,
but __cdecl methods require putting both parameters on the stack in
opposite order.
Using a special calling convention allows frontends to keep the sret
parameter first, which avoids breaking lots of assumptions in LLVM and
Clang.
Fixes PR15768 with the corresponding change in Clang.
Reviewers: ributzka, majnemer
Differential Revision: http://llvm-reviews.chandlerc.com/D2663
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200561 91177308-0d34-0410-b5e6-96231b3b80d8
-rw-r--r-- | docs/BitCodeFormat.rst | 2 | ||||
-rw-r--r-- | docs/CodeGenerator.rst | 4 | ||||
-rw-r--r-- | include/llvm/IR/CallingConv.h | 8 | ||||
-rw-r--r-- | lib/AsmParser/LLLexer.cpp | 1 | ||||
-rw-r--r-- | lib/AsmParser/LLParser.cpp | 2 | ||||
-rw-r--r-- | lib/AsmParser/LLToken.h | 2 | ||||
-rw-r--r-- | lib/IR/AsmWriter.cpp | 1 | ||||
-rw-r--r-- | lib/Target/X86/X86CallingConv.h | 27 | ||||
-rw-r--r-- | lib/Target/X86/X86CallingConv.td | 10 | ||||
-rw-r--r-- | test/CodeGen/X86/cdecl-method-return.ll | 69 |
10 files changed, 124 insertions, 2 deletions
diff --git a/docs/BitCodeFormat.rst b/docs/BitCodeFormat.rst index 38b4010483..4c1c94abd6 100644 --- a/docs/BitCodeFormat.rst +++ b/docs/BitCodeFormat.rst @@ -746,6 +746,8 @@ function. The operand fields are: * ``arm_apcscc``: code 66 * ``arm_aapcscc``: code 67 * ``arm_aapcs_vfpcc``: code 68 + * ``x86_thiscallcc``: code 70 + * ``x86_cdeclmethodcc``: code 80 * isproto*: Non-zero if this entry represents a declaration rather than a definition diff --git a/docs/CodeGenerator.rst b/docs/CodeGenerator.rst index b89d2f426f..d7d98bc385 100644 --- a/docs/CodeGenerator.rst +++ b/docs/CodeGenerator.rst @@ -2145,6 +2145,10 @@ The following target-specific calling conventions are known to backend: others via stack. Callee is responsible for stack cleaning. This convention is used by MSVC by default for methods in its ABI (CC ID = 70). +* **X86_CDeclMethod** --- Identical to the standard x86_32 C calling convention, + except that an sret paramter, if present, is placed on the stack after the + second parameter, which must an integer or pointer. (CC ID = 80). + .. _X86 addressing mode: Representing X86 addressing modes in MachineInstrs diff --git a/include/llvm/IR/CallingConv.h b/include/llvm/IR/CallingConv.h index 1eaf4f7f46..af44e8a30c 100644 --- a/include/llvm/IR/CallingConv.h +++ b/include/llvm/IR/CallingConv.h @@ -137,7 +137,13 @@ namespace CallingConv { /// convention differs from the more common \c X86_64_SysV convention /// in a number of ways, most notably in that XMM registers used to pass /// arguments are shadowed by GPRs, and vice versa. - X86_64_Win64 = 79 + X86_64_Win64 = 79, + + /// \brief The calling convention used for __cdecl methods on win32. + /// Differs from the C calling convention only in that the order of the + /// first parameter and the sret parameter are swapped. + X86_CDeclMethod = 80 + }; } // End CallingConv namespace diff --git a/lib/AsmParser/LLLexer.cpp b/lib/AsmParser/LLLexer.cpp index 7fb8032ca9..00b137d5a7 100644 --- a/lib/AsmParser/LLLexer.cpp +++ b/lib/AsmParser/LLLexer.cpp @@ -550,6 +550,7 @@ lltok::Kind LLLexer::LexIdentifier() { KEYWORD(x86_stdcallcc); KEYWORD(x86_fastcallcc); KEYWORD(x86_thiscallcc); + KEYWORD(x86_cdeclmethodcc); KEYWORD(arm_apcscc); KEYWORD(arm_aapcscc); KEYWORD(arm_aapcs_vfpcc); diff --git a/lib/AsmParser/LLParser.cpp b/lib/AsmParser/LLParser.cpp index ab4b48bf6e..b36f0e840c 100644 --- a/lib/AsmParser/LLParser.cpp +++ b/lib/AsmParser/LLParser.cpp @@ -1357,6 +1357,7 @@ bool LLParser::ParseOptionalDLLStorageClass(unsigned &Res) { /// ::= 'x86_stdcallcc' /// ::= 'x86_fastcallcc' /// ::= 'x86_thiscallcc' +/// ::= 'x86_cdeclmethodcc' /// ::= 'arm_apcscc' /// ::= 'arm_aapcscc' /// ::= 'arm_aapcs_vfpcc' @@ -1382,6 +1383,7 @@ bool LLParser::ParseOptionalCallingConv(CallingConv::ID &CC) { case lltok::kw_x86_stdcallcc: CC = CallingConv::X86_StdCall; break; case lltok::kw_x86_fastcallcc: CC = CallingConv::X86_FastCall; break; case lltok::kw_x86_thiscallcc: CC = CallingConv::X86_ThisCall; break; + case lltok::kw_x86_cdeclmethodcc:CC = CallingConv::X86_CDeclMethod; break; case lltok::kw_arm_apcscc: CC = CallingConv::ARM_APCS; break; case lltok::kw_arm_aapcscc: CC = CallingConv::ARM_AAPCS; break; case lltok::kw_arm_aapcs_vfpcc:CC = CallingConv::ARM_AAPCS_VFP; break; diff --git a/lib/AsmParser/LLToken.h b/lib/AsmParser/LLToken.h index 50318500bf..67f2c0c42b 100644 --- a/lib/AsmParser/LLToken.h +++ b/lib/AsmParser/LLToken.h @@ -85,7 +85,7 @@ namespace lltok { kw_cc, kw_ccc, kw_fastcc, kw_coldcc, kw_intel_ocl_bicc, - kw_x86_stdcallcc, kw_x86_fastcallcc, kw_x86_thiscallcc, + kw_x86_stdcallcc, kw_x86_fastcallcc, kw_x86_thiscallcc, kw_x86_cdeclmethodcc, kw_arm_apcscc, kw_arm_aapcscc, kw_arm_aapcs_vfpcc, kw_msp430_intrcc, kw_ptx_kernel, kw_ptx_device, diff --git a/lib/IR/AsmWriter.cpp b/lib/IR/AsmWriter.cpp index 2b23278a88..c48214cc2f 100644 --- a/lib/IR/AsmWriter.cpp +++ b/lib/IR/AsmWriter.cpp @@ -78,6 +78,7 @@ static void PrintCallingConv(unsigned cc, raw_ostream &Out) { case CallingConv::X86_StdCall: Out << "x86_stdcallcc"; break; case CallingConv::X86_FastCall: Out << "x86_fastcallcc"; break; case CallingConv::X86_ThisCall: Out << "x86_thiscallcc"; break; + case CallingConv::X86_CDeclMethod:Out << "x86_cdeclmethodcc"; break; case CallingConv::Intel_OCL_BI: Out << "intel_ocl_bicc"; break; case CallingConv::ARM_APCS: Out << "arm_apcscc"; break; case CallingConv::ARM_AAPCS: Out << "arm_aapcscc"; break; diff --git a/lib/Target/X86/X86CallingConv.h b/lib/Target/X86/X86CallingConv.h index e76f9fda2d..040da3535e 100644 --- a/lib/Target/X86/X86CallingConv.h +++ b/lib/Target/X86/X86CallingConv.h @@ -29,6 +29,33 @@ inline bool CC_X86_AnyReg_Error(unsigned &, MVT &, MVT &, return false; } +inline bool CC_X86_CDeclMethod_SRet(unsigned &ValNo, MVT &ValVT, MVT &LocVT, + CCValAssign::LocInfo &LocInfo, + ISD::ArgFlagsTy &ArgFlags, CCState &State) { + // Swap the order of the first two parameters if the first parameter is sret. + if (ArgFlags.isSRet()) { + assert(ValNo == 0); + assert(ValVT == MVT::i32); + State.AllocateStack(8, 4); + State.addLoc(CCValAssign::getCustomMem(ValNo, ValVT, 4, LocVT, LocInfo)); + + // Indicate that we need to swap the order of the first and second + // parameters by "allocating" register zero. There are no register + // parameters with cdecl methods, so we can use this to communicate to the + // next call. + State.AllocateReg(1); + return true; + } else if (ValNo == 1 && State.isAllocated(1)) { + assert(ValVT == MVT::i32 && "non-i32-sized this param unsupported"); + // Stack was already allocated while processing sret. + State.addLoc(CCValAssign::getCustomMem(ValNo, ValVT, 0, LocVT, LocInfo)); + return true; + } + + // All other args use the C calling convention. + return false; +} + } // End llvm namespace #endif diff --git a/lib/Target/X86/X86CallingConv.td b/lib/Target/X86/X86CallingConv.td index 5b51a1e8e0..f40a42ee9b 100644 --- a/lib/Target/X86/X86CallingConv.td +++ b/lib/Target/X86/X86CallingConv.td @@ -485,6 +485,15 @@ def CC_X86_32_ThisCall_Win : CallingConv<[ CCDelegateTo<CC_X86_32_ThisCall_Common> ]>; +def CC_X86_CDeclMethod : CallingConv<[ + // Promote i8/i16 arguments to i32. + CCIfType<[i8, i16], CCPromoteToType<i32>>, + + CCCustom<"CC_X86_CDeclMethod_SRet">, + + CCDelegateTo<CC_X86_32_Common> +]>; + def CC_X86_32_ThisCall : CallingConv<[ CCIfSubtarget<"isTargetCygMing()", CCDelegateTo<CC_X86_32_ThisCall_Mingw>>, CCDelegateTo<CC_X86_32_ThisCall_Win> @@ -574,6 +583,7 @@ def CC_Intel_OCL_BI : CallingConv<[ def CC_X86_32 : CallingConv<[ CCIfCC<"CallingConv::X86_FastCall", CCDelegateTo<CC_X86_32_FastCall>>, CCIfCC<"CallingConv::X86_ThisCall", CCDelegateTo<CC_X86_32_ThisCall>>, + CCIfCC<"CallingConv::X86_CDeclMethod", CCDelegateTo<CC_X86_CDeclMethod>>, CCIfCC<"CallingConv::Fast", CCDelegateTo<CC_X86_32_FastCC>>, CCIfCC<"CallingConv::GHC", CCDelegateTo<CC_X86_32_GHC>>, CCIfCC<"CallingConv::HiPE", CCDelegateTo<CC_X86_32_HiPE>>, diff --git a/test/CodeGen/X86/cdecl-method-return.ll b/test/CodeGen/X86/cdecl-method-return.ll new file mode 100644 index 0000000000..e7af59737e --- /dev/null +++ b/test/CodeGen/X86/cdecl-method-return.ll @@ -0,0 +1,69 @@ +; RUN: llc < %s -mtriple=i686-pc-win32 | FileCheck %s + +; The sret flag causes the first two parameters to be reordered on the stack. + +define x86_cdeclmethodcc void @foo(i32* sret %dst, i32* %src) { + %v = load i32* %src + store i32 %v, i32* %dst + ret void +} + +; CHECK-LABEL: _foo: +; CHECK: movl 8(%esp), %[[dst:[^ ]*]] +; CHECK: movl 4(%esp), %[[src:[^ ]*]] +; CHECK: movl (%[[src]]), %[[v:[^ ]*]] +; CHECK: movl %[[v]], (%[[dst]]) +; CHECK: retl + +define i32 @bar() { + %src = alloca i32 + %dst = alloca i32 + store i32 42, i32* %src + call x86_cdeclmethodcc void @foo(i32* sret %dst, i32* %src) + %v = load i32* %dst + ret i32 %v +} + +; CHECK-LABEL: _bar: +; CHECK: movl $42, [[src:[^,]*]] +; CHECK: leal [[src]], %[[reg:[^ ]*]] +; CHECK: movl %[[reg]], (%esp) +; CHECK: leal [[dst:[^,]*]], %[[reg:[^ ]*]] +; CHECK: movl %[[reg]], 4(%esp) +; CHECK: calll _foo +; CHECK: movl [[dst]], %eax +; CHECK: retl + +; If we don't have the sret flag, parameters are not reordered. + +define x86_cdeclmethodcc void @baz(i32* %dst, i32* %src) { + %v = load i32* %src + store i32 %v, i32* %dst + ret void +} + +; CHECK-LABEL: _baz: +; CHECK: movl 4(%esp), %[[dst:[^ ]*]] +; CHECK: movl 8(%esp), %[[src:[^ ]*]] +; CHECK: movl (%[[src]]), %[[v:[^ ]*]] +; CHECK: movl %[[v]], (%[[dst]]) +; CHECK: retl + +define i32 @qux() { + %src = alloca i32 + %dst = alloca i32 + store i32 42, i32* %src + call x86_cdeclmethodcc void @baz(i32* %dst, i32* %src) + %v = load i32* %dst + ret i32 %v +} + +; CHECK-LABEL: _qux: +; CHECK: movl $42, [[src:[^,]*]] +; CHECK: leal [[src]], %[[reg:[^ ]*]] +; CHECK: movl %[[reg]], 4(%esp) +; CHECK: leal [[dst:[^,]*]], %[[reg:[^ ]*]] +; CHECK: movl %[[reg]], (%esp) +; CHECK: calll _baz +; CHECK: movl [[dst]], %eax +; CHECK: retl |