Add two new calling conventions for runtime calls

This patch adds two new target-independent calling conventions for runtime
calls - PreserveMost and PreserveAll.
The target-specific implementation for X86-64 is defined as following:
  - Arguments are passed as for the default C calling convention
  - The same applies for the return value(s)
  - PreserveMost preserves all GPRs - except R11
  - PreserveAll preserves all GPRs and all XMMs/YMMs - except R11

Reviewed by Lang and Philip

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199508 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Juergen Ributzka 2014-01-17 19:47:03 +00:00
parent 41e1c04201
commit ceaf829339
11 changed files with 274 additions and 0 deletions

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@ -739,6 +739,8 @@ function. The operand fields are:
* ``coldcc``: code 9
* ``webkit_jscc``: code 12
* ``anyregcc``: code 13
* ``preserve_mostcc``: code 14
* ``preserve_allcc``: code 15
* ``x86_stdcallcc``: code 64
* ``x86_fastcallcc``: code 65
* ``arm_apcscc``: code 66

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@ -359,6 +359,49 @@ added in the future:
allocated. This can currently only be used with calls to
llvm.experimental.patchpoint because only this intrinsic records
the location of its arguments in a side table. See :doc:`StackMaps`.
"``preserve_mostcc``" - The `PreserveMost` calling convention
This calling convention attempts to make the code in the caller as little
intrusive as possible. This calling convention behaves identical to the `C`
calling convention on how arguments and return values are passed, but it
uses a different set of caller/callee-saved registers. This alleviates the
burden of saving and recovering a large register set before and after the
call in the caller.
- On X86-64 the callee preserves all general purpose registers, except for
R11. R11 can be used as a scratch register. Floating-point registers
(XMMs/YMMs) are not preserved and need to be saved by the caller.
The idea behind this convention is to support calls to runtime functions
that have a hot path and a cold path. The hot path is usually a small piece
of code that doesn't many registers. The cold path might need to call out to
another function and therefore only needs to preserve the caller-saved
registers, which haven't already been saved by the caller.
This calling convention will be used by a future version of the ObjectiveC
runtime and should therefore still be considered experimental at this time.
Although this convention was created to optimize certain runtime calls to
the ObjectiveC runtime, it is not limited to this runtime and might be used
by other runtimes in the future too. The current implementation only
supports X86-64, but the intention is to support more architectures in the
future.
"``preserve_allcc``" - The `PreserveAll` calling convention
This calling convention attempts to make the code in the caller even less
intrusive than the `PreserveMost` calling convention. This calling
convention also behaves identical to the `C` calling convention on how
arguments and return values are passed, but it uses a different set of
caller/callee-saved registers. This removes the burden of saving and
recovering a large register set before and after the call in the caller.
- On X86-64 the callee preserves all general purpose registers, except for
R11. R11 can be used as a scratch register. Furthermore it also preserves
all floating-point registers (XMMs/YMMs).
The idea behind this convention is to support calls to runtime functions
that don't need to call out to any other functions.
This calling convention, like the `PreserveMost` calling convention, will be
used by a future version of the ObjectiveC runtime and should be considered
experimental at this time.
"``cc <n>``" - Numbered convention
Any calling convention may be specified by number, allowing
target-specific calling conventions to be used. Target specific

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@ -58,6 +58,14 @@ namespace CallingConv {
// stackmap and patchpoint intrinsics).
AnyReg = 13,
// PreserveMost - Calling convention for runtime calls that preserves most
// registers.
PreserveMost = 14,
// PreserveAll - Calling convention for runtime calls that preserves
// (almost) all registers.
PreserveAll = 15,
// Target - This is the start of the target-specific calling conventions,
// e.g. fastcall and thiscall on X86.
FirstTargetCC = 64,

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@ -563,6 +563,8 @@ lltok::Kind LLLexer::LexIdentifier() {
KEYWORD(x86_64_win64cc);
KEYWORD(webkit_jscc);
KEYWORD(anyregcc);
KEYWORD(preserve_mostcc);
KEYWORD(preserve_allcc);
KEYWORD(cc);
KEYWORD(c);

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@ -1369,6 +1369,8 @@ bool LLParser::ParseOptionalDLLStorageClass(unsigned &Res) {
/// ::= 'x86_64_win64cc'
/// ::= 'webkit_jscc'
/// ::= 'anyregcc'
/// ::= 'preserve_mostcc'
/// ::= 'preserve_allcc'
/// ::= 'cc' UINT
///
bool LLParser::ParseOptionalCallingConv(CallingConv::ID &CC) {
@ -1393,6 +1395,8 @@ bool LLParser::ParseOptionalCallingConv(CallingConv::ID &CC) {
case lltok::kw_x86_64_win64cc: CC = CallingConv::X86_64_Win64; break;
case lltok::kw_webkit_jscc: CC = CallingConv::WebKit_JS; break;
case lltok::kw_anyregcc: CC = CallingConv::AnyReg; break;
case lltok::kw_preserve_mostcc:CC = CallingConv::PreserveMost; break;
case lltok::kw_preserve_allcc: CC = CallingConv::PreserveAll; break;
case lltok::kw_cc: {
unsigned ArbitraryCC;
Lex.Lex();

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@ -92,6 +92,7 @@ namespace lltok {
kw_spir_kernel, kw_spir_func,
kw_x86_64_sysvcc, kw_x86_64_win64cc,
kw_webkit_jscc, kw_anyregcc,
kw_preserve_mostcc, kw_preserve_allcc,
// Attributes:
kw_attributes,

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@ -73,6 +73,8 @@ static void PrintCallingConv(unsigned cc, raw_ostream &Out) {
case CallingConv::Cold: Out << "coldcc"; break;
case CallingConv::WebKit_JS: Out << "webkit_jscc"; break;
case CallingConv::AnyReg: Out << "anyregcc"; break;
case CallingConv::PreserveMost: Out << "preserve_mostcc"; break;
case CallingConv::PreserveAll: Out << "preserve_allcc"; break;
case CallingConv::X86_StdCall: Out << "x86_stdcallcc"; break;
case CallingConv::X86_FastCall: Out << "x86_fastcallcc"; break;
case CallingConv::X86_ThisCall: Out << "x86_thiscallcc"; break;

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@ -620,6 +620,16 @@ def CSR_64EHRet : CalleeSavedRegs<(add RAX, RDX, CSR_64)>;
def CSR_Win64 : CalleeSavedRegs<(add RBX, RBP, RDI, RSI, R12, R13, R14, R15,
(sequence "XMM%u", 6, 15))>;
// All GPRs - except r11
def CSR_64_RT_MostRegs : CalleeSavedRegs<(add CSR_64, RAX, RCX, RDX, RSI, RDI,
R8, R9, R10, RSP)>;
// All registers - except r11
def CSR_64_RT_AllRegs : CalleeSavedRegs<(add CSR_64_RT_MostRegs,
(sequence "XMM%u", 0, 15))>;
def CSR_64_RT_AllRegs_AVX : CalleeSavedRegs<(add CSR_64_RT_MostRegs,
(sequence "YMM%u", 0, 15))>;
def CSR_64_MostRegs : CalleeSavedRegs<(add RBX, RCX, RDX, RSI, RDI, R8, R9, R10,
R11, R12, R13, R14, R15, RBP,
(sequence "XMM%u", 0, 15))>;

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@ -245,6 +245,12 @@ X86RegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
if (HasAVX)
return CSR_64_AllRegs_AVX_SaveList;
return CSR_64_AllRegs_SaveList;
case CallingConv::PreserveMost:
return CSR_64_RT_MostRegs_SaveList;
case CallingConv::PreserveAll:
if (HasAVX)
return CSR_64_RT_AllRegs_AVX_SaveList;
return CSR_64_RT_AllRegs_SaveList;
case CallingConv::Intel_OCL_BI: {
if (HasAVX512 && IsWin64)
return CSR_Win64_Intel_OCL_BI_AVX512_SaveList;
@ -292,6 +298,12 @@ X86RegisterInfo::getCallPreservedMask(CallingConv::ID CC) const {
if (HasAVX)
return CSR_64_AllRegs_AVX_RegMask;
return CSR_64_AllRegs_RegMask;
case CallingConv::PreserveMost:
return CSR_64_RT_MostRegs_RegMask;
case CallingConv::PreserveAll:
if (HasAVX)
return CSR_64_RT_AllRegs_AVX_RegMask;
return CSR_64_RT_AllRegs_RegMask;
case CallingConv::Intel_OCL_BI: {
if (IsWin64 && HasAVX512)
return CSR_Win64_Intel_OCL_BI_AVX512_RegMask;

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@ -0,0 +1,104 @@
; RUN: llc < %s -mtriple=x86_64-apple-darwin -mcpu=corei7 | FileCheck --check-prefix=SSE %s
; RUN: llc < %s -mtriple=x86_64-apple-darwin -mcpu=corei7-avx | FileCheck --check-prefix=AVX %s
define preserve_allcc void @preserve_allcc1() nounwind {
entry:
;SSE-LABEL: preserve_allcc1
;SSE: pushq %r10
;SSE-NEXT: pushq %r9
;SSE-NEXT: pushq %r8
;SSE-NEXT: pushq %rdi
;SSE-NEXT: pushq %rsi
;SSE-NEXT: pushq %rdx
;SSE-NEXT: pushq %rcx
;SSE-NEXT: pushq %rax
;SSE-NEXT: pushq %rbp
;SSE-NEXT: pushq %r15
;SSE-NEXT: pushq %r14
;SSE-NEXT: pushq %r13
;SSE-NEXT: pushq %r12
;SSE-NEXT: pushq %rbx
;SSE: movaps %xmm15
;SSE-NEXT: movaps %xmm14
;SSE-NEXT: movaps %xmm13
;SSE-NEXT: movaps %xmm12
;SSE-NEXT: movaps %xmm11
;SSE-NEXT: movaps %xmm10
;SSE-NEXT: movaps %xmm9
;SSE-NEXT: movaps %xmm8
;SSE-NEXT: movaps %xmm7
;SSE-NEXT: movaps %xmm6
;SSE-NEXT: movaps %xmm5
;SSE-NEXT: movaps %xmm4
;SSE-NEXT: movaps %xmm3
;SSE-NEXT: movaps %xmm2
;SSE-NEXT: movaps %xmm1
;SSE-NEXT: movaps %xmm0
;AVX-LABEL: preserve_allcc1
;AVX: pushq %r10
;AVX-NEXT: pushq %r9
;AVX-NEXT: pushq %r8
;AVX-NEXT: pushq %rdi
;AVX-NEXT: pushq %rsi
;AVX-NEXT: pushq %rdx
;AVX-NEXT: pushq %rcx
;AVX-NEXT: pushq %rax
;AVX-NEXT: pushq %rbp
;AVX-NEXT: pushq %r15
;AVX-NEXT: pushq %r14
;AVX-NEXT: pushq %r13
;AVX-NEXT: pushq %r12
;AVX-NEXT: pushq %rbx
;AVX: vmovups %ymm15
;AVX-NEXT: vmovups %ymm14
;AVX-NEXT: vmovups %ymm13
;AVX-NEXT: vmovups %ymm12
;AVX-NEXT: vmovups %ymm11
;AVX-NEXT: vmovups %ymm10
;AVX-NEXT: vmovups %ymm9
;AVX-NEXT: vmovups %ymm8
;AVX-NEXT: vmovups %ymm7
;AVX-NEXT: vmovups %ymm6
;AVX-NEXT: vmovups %ymm5
;AVX-NEXT: vmovups %ymm4
;AVX-NEXT: vmovups %ymm3
;AVX-NEXT: vmovups %ymm2
;AVX-NEXT: vmovups %ymm1
;AVX-NEXT: vmovups %ymm0
call void asm sideeffect "", "~{rax},~{rbx},~{rcx},~{rdx},~{rsi},~{rdi},~{r8},~{r9},~{r10},~{r11},~{r12},~{r13},~{r14},~{r15},~{rbp},~{xmm0},~{xmm1},~{xmm2},~{xmm3},~{xmm4},~{xmm5},~{xmm6},~{xmm7},~{xmm8},~{xmm9},~{xmm10},~{xmm11},~{xmm12},~{xmm13},~{xmm14},~{xmm15}"()
ret void
}
; Make sure only R11 is saved before the call
declare preserve_allcc void @bar(i64, i64, double, double)
define void @preserve_allcc2() nounwind {
entry:
;SSE-LABEL: preserve_allcc2
;SSE: movq %r11, [[REG:%[a-z0-9]+]]
;SSE-NOT: movaps %xmm
;SSE: movq [[REG]], %r11
%a0 = call i64 asm sideeffect "", "={rax}"() nounwind
%a1 = call i64 asm sideeffect "", "={rcx}"() nounwind
%a2 = call i64 asm sideeffect "", "={rdx}"() nounwind
%a3 = call i64 asm sideeffect "", "={r8}"() nounwind
%a4 = call i64 asm sideeffect "", "={r9}"() nounwind
%a5 = call i64 asm sideeffect "", "={r10}"() nounwind
%a6 = call i64 asm sideeffect "", "={r11}"() nounwind
%a10 = call <2 x double> asm sideeffect "", "={xmm2}"() nounwind
%a11 = call <2 x double> asm sideeffect "", "={xmm3}"() nounwind
%a12 = call <2 x double> asm sideeffect "", "={xmm4}"() nounwind
%a13 = call <2 x double> asm sideeffect "", "={xmm5}"() nounwind
%a14 = call <2 x double> asm sideeffect "", "={xmm6}"() nounwind
%a15 = call <2 x double> asm sideeffect "", "={xmm7}"() nounwind
%a16 = call <2 x double> asm sideeffect "", "={xmm8}"() nounwind
%a17 = call <2 x double> asm sideeffect "", "={xmm9}"() nounwind
%a18 = call <2 x double> asm sideeffect "", "={xmm10}"() nounwind
%a19 = call <2 x double> asm sideeffect "", "={xmm11}"() nounwind
%a20 = call <2 x double> asm sideeffect "", "={xmm12}"() nounwind
%a21 = call <2 x double> asm sideeffect "", "={xmm13}"() nounwind
%a22 = call <2 x double> asm sideeffect "", "={xmm14}"() nounwind
%a23 = call <2 x double> asm sideeffect "", "={xmm15}"() nounwind
call preserve_allcc void @bar(i64 1, i64 2, double 3.0, double 4.0)
call void asm sideeffect "", "{rax},{rcx},{rdx},{r8},{r9},{r10},{r11},{xmm2},{xmm3},{xmm4},{xmm5},{xmm6},{xmm7},{xmm8},{xmm9},{xmm10},{xmm11},{xmm12},{xmm13},{xmm14},{xmm15}"(i64 %a0, i64 %a1, i64 %a2, i64 %a3, i64 %a4, i64 %a5, i64 %a6, <2 x double> %a10, <2 x double> %a11, <2 x double> %a12, <2 x double> %a13, <2 x double> %a14, <2 x double> %a15, <2 x double> %a16, <2 x double> %a17, <2 x double> %a18, <2 x double> %a19, <2 x double> %a20, <2 x double> %a21, <2 x double> %a22, <2 x double> %a23)
ret void
}

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@ -0,0 +1,86 @@
; RUN: llc < %s -mtriple=x86_64-apple-darwin -mcpu=corei7 | FileCheck --check-prefix=SSE %s
; RUN: llc < %s -mtriple=x86_64-apple-darwin -mcpu=corei7-avx | FileCheck --check-prefix=AVX %s
; Every GPR should be saved - except r11
define preserve_mostcc void @preserve_mostcc1() nounwind {
entry:
;SSE-LABEL: preserve_mostcc1
;SSE: pushq %r10
;SSE-NEXT: pushq %r9
;SSE-NEXT: pushq %r8
;SSE-NEXT: pushq %rdi
;SSE-NEXT: pushq %rsi
;SSE-NEXT: pushq %rdx
;SSE-NEXT: pushq %rcx
;SSE-NEXT: pushq %rax
;SSE-NEXT: pushq %rbp
;SSE-NEXT: pushq %r15
;SSE-NEXT: pushq %r14
;SSE-NEXT: pushq %r13
;SSE-NEXT: pushq %r12
;SSE-NEXT: pushq %rbx
;AVX-LABEL: preserve_mostcc1
;AVX: pushq %r10
;AVX-NEXT: pushq %r9
;AVX-NEXT: pushq %r8
;AVX-NEXT: pushq %rdi
;AVX-NEXT: pushq %rsi
;AVX-NEXT: pushq %rdx
;AVX-NEXT: pushq %rcx
;AVX-NEXT: pushq %rax
;AVX-NEXT: pushq %rbp
;AVX-NEXT: pushq %r15
;AVX-NEXT: pushq %r14
;AVX-NEXT: pushq %r13
;AVX-NEXT: pushq %r12
;AVX-NEXT: pushq %rbx
call void asm sideeffect "", "~{rax},~{rbx},~{rcx},~{rdx},~{rsi},~{rdi},~{r8},~{r9},~{r10},~{r11},~{r12},~{r13},~{r14},~{r15},~{rbp},~{xmm0},~{xmm1},~{xmm2},~{xmm3},~{xmm4},~{xmm5},~{xmm6},~{xmm7},~{xmm8},~{xmm9},~{xmm10},~{xmm11},~{xmm12},~{xmm13},~{xmm14},~{xmm15}"()
ret void
}
; Make sure R11 and XMMs are saved before the call
declare preserve_mostcc void @foo(i64, i64, double, double)
define void @preserve_mostcc2() nounwind {
entry:
;SSE-LABEL: preserve_mostcc2
;SSE: movq %r11, [[REG:%[a-z0-9]+]]
;SSE: movaps %xmm2
;SSE: movaps %xmm3
;SSE: movaps %xmm4
;SSE: movaps %xmm5
;SSE: movaps %xmm6
;SSE: movaps %xmm7
;SSE: movaps %xmm8
;SSE: movaps %xmm9
;SSE: movaps %xmm10
;SSE: movaps %xmm11
;SSE: movaps %xmm12
;SSE: movaps %xmm13
;SSE: movaps %xmm14
;SSE: movaps %xmm15
;SSE: movq [[REG]], %r11
%a0 = call i64 asm sideeffect "", "={rax}"() nounwind
%a1 = call i64 asm sideeffect "", "={rcx}"() nounwind
%a2 = call i64 asm sideeffect "", "={rdx}"() nounwind
%a3 = call i64 asm sideeffect "", "={r8}"() nounwind
%a4 = call i64 asm sideeffect "", "={r9}"() nounwind
%a5 = call i64 asm sideeffect "", "={r10}"() nounwind
%a6 = call i64 asm sideeffect "", "={r11}"() nounwind
%a10 = call <2 x double> asm sideeffect "", "={xmm2}"() nounwind
%a11 = call <2 x double> asm sideeffect "", "={xmm3}"() nounwind
%a12 = call <2 x double> asm sideeffect "", "={xmm4}"() nounwind
%a13 = call <2 x double> asm sideeffect "", "={xmm5}"() nounwind
%a14 = call <2 x double> asm sideeffect "", "={xmm6}"() nounwind
%a15 = call <2 x double> asm sideeffect "", "={xmm7}"() nounwind
%a16 = call <2 x double> asm sideeffect "", "={xmm8}"() nounwind
%a17 = call <2 x double> asm sideeffect "", "={xmm9}"() nounwind
%a18 = call <2 x double> asm sideeffect "", "={xmm10}"() nounwind
%a19 = call <2 x double> asm sideeffect "", "={xmm11}"() nounwind
%a20 = call <2 x double> asm sideeffect "", "={xmm12}"() nounwind
%a21 = call <2 x double> asm sideeffect "", "={xmm13}"() nounwind
%a22 = call <2 x double> asm sideeffect "", "={xmm14}"() nounwind
%a23 = call <2 x double> asm sideeffect "", "={xmm15}"() nounwind
call preserve_mostcc void @foo(i64 1, i64 2, double 3.0, double 4.0)
call void asm sideeffect "", "{rax},{rcx},{rdx},{r8},{r9},{r10},{r11},{xmm2},{xmm3},{xmm4},{xmm5},{xmm6},{xmm7},{xmm8},{xmm9},{xmm10},{xmm11},{xmm12},{xmm13},{xmm14},{xmm15}"(i64 %a0, i64 %a1, i64 %a2, i64 %a3, i64 %a4, i64 %a5, i64 %a6, <2 x double> %a10, <2 x double> %a11, <2 x double> %a12, <2 x double> %a13, <2 x double> %a14, <2 x double> %a15, <2 x double> %a16, <2 x double> %a17, <2 x double> %a18, <2 x double> %a19, <2 x double> %a20, <2 x double> %a21, <2 x double> %a22, <2 x double> %a23)
ret void
}