From: Renato Golin Date: Wed, 26 Mar 2014 12:52:28 +0000 (+0000) Subject: Add @llvm.clear_cache builtin X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=c4b058f9e7145765783fb741ea280acc4fea1f94;p=oota-llvm.git Add @llvm.clear_cache builtin Implementing the LLVM part of the call to __builtin___clear_cache which translates into an intrinsic @llvm.clear_cache and is lowered by each target, either to a call to __clear_cache or nothing at all incase the caches are unified. Updating LangRef and adding some tests for the implemented architectures. Other archs will have to implement the method in case this builtin has to be compiled for it, since the default behaviour is to bail unimplemented. A Clang patch is required for the builtin to be lowered into the llvm intrinsic. This will be done next. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204802 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/docs/LangRef.rst b/docs/LangRef.rst index c959f56ef11..d18d4ebac90 100644 --- a/docs/LangRef.rst +++ b/docs/LangRef.rst @@ -6939,6 +6939,36 @@ is lowered to a constant 0. Note that runtime support may be conditional on the privilege-level code is running at and the host platform. +'``llvm.clear_cache``' Intrinsic +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Syntax: +""""""" + +:: + + declare void @llvm.clear_cache(i8*, i8*) + +Overview: +""""""""" + +The '``llvm.clear_cache``' intrinsic provides access to the systemcall +that flushes the cache at the range specified. Some targets need this +to specifically flush the instruction cache when executable data changes +in memory (self-modifying code). Other targets have unified intruction +and data cache, so they don't need any calls. + +Semantics: +"""""""""" + +When directly supported, this intrinsic will either return a call to +the appropriate cache clearing system call (usually ``__clear_cache``) +when the caches are not unified (ARM, Mips) or just remove the call +altogether when they are (ex. x86_64). + +Targets must implement it directly to have either behaviour, as the +default is to bail with "Not Implemented" message. + Standard C Library Intrinsics ----------------------------- diff --git a/include/llvm/IR/Intrinsics.td b/include/llvm/IR/Intrinsics.td index 94c7b50ac8e..0c9cc3be3d7 100644 --- a/include/llvm/IR/Intrinsics.td +++ b/include/llvm/IR/Intrinsics.td @@ -513,6 +513,11 @@ def int_convertus : Intrinsic<[llvm_anyint_ty], def int_convertuu : Intrinsic<[llvm_anyint_ty], [llvm_anyint_ty, llvm_i32_ty, llvm_i32_ty]>; +// Clear cache intrinsic, default to ignore (ie. emit nothing) +// maps to void __clear_cache() on supporting platforms +def int_clear_cache : Intrinsic<[], [llvm_ptr_ty, llvm_ptr_ty], + [], "llvm.clear_cache">; + //===----------------------------------------------------------------------===// // Target-specific intrinsics //===----------------------------------------------------------------------===// diff --git a/include/llvm/Target/TargetLowering.h b/include/llvm/Target/TargetLowering.h index 8f00ac8fa33..fbc8b74e9e7 100644 --- a/include/llvm/Target/TargetLowering.h +++ b/include/llvm/Target/TargetLowering.h @@ -2108,6 +2108,11 @@ public: return false; } + /// Return the builtin name for the __builtin___clear_cache intrinsic + virtual const char * getClearCacheBuiltinName() const { + llvm_unreachable("Not Implemented"); + } + /// Return the type that should be used to zero or sign extend a /// zeroext/signext integer argument or return value. FIXME: Most C calling /// convention requires the return type to be promoted, but this is not true diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp index bd80a503e21..639ff82ffd3 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -5386,6 +5386,8 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) { (void)getControlRoot(); return 0; } + case Intrinsic::clear_cache: + return TLI->getClearCacheBuiltinName(); case Intrinsic::donothing: // ignore return 0; diff --git a/lib/Target/ARM/ARMISelLowering.h b/lib/Target/ARM/ARMISelLowering.h index 022945f625a..5f6ea754348 100644 --- a/lib/Target/ARM/ARMISelLowering.h +++ b/lib/Target/ARM/ARMISelLowering.h @@ -384,6 +384,11 @@ namespace llvm { bool shouldConvertConstantLoadToIntImm(const APInt &Imm, Type *Ty) const override; + /// Clear cache library call + const char * getClearCacheBuiltinName() const { + return "__clear_cache"; + } + protected: std::pair findRepresentativeClass(MVT VT) const override; diff --git a/lib/Target/Mips/MipsISelLowering.h b/lib/Target/Mips/MipsISelLowering.h index 27492a8046c..b03cccfb586 100644 --- a/lib/Target/Mips/MipsISelLowering.h +++ b/lib/Target/Mips/MipsISelLowering.h @@ -583,6 +583,11 @@ namespace llvm { bool MemcpyStrSrc, MachineFunction &MF) const; + /// Clear cache library call + const char * getClearCacheBuiltinName() const { + return "__clear_cache"; + } + /// isFPImmLegal - Returns true if the target can instruction select the /// specified FP immediate natively. If false, the legalizer will /// materialize the FP immediate as a load from a constant pool. diff --git a/lib/Target/X86/X86ISelLowering.h b/lib/Target/X86/X86ISelLowering.h index 894cfc6d0c1..ae13ca491cb 100644 --- a/lib/Target/X86/X86ISelLowering.h +++ b/lib/Target/X86/X86ISelLowering.h @@ -770,6 +770,11 @@ namespace llvm { bool shouldConvertConstantLoadToIntImm(const APInt &Imm, Type *Ty) const override; + /// Intel processors have a unified instruction and data cache + const char * getClearCacheBuiltinName() const { + return 0; // nothing to do, move along. + } + /// createFastISel - This method returns a target specific FastISel object, /// or null if the target does not support "fast" ISel. FastISel *createFastISel(FunctionLoweringInfo &funcInfo, diff --git a/test/CodeGen/ARM/cache-intrinsic.ll b/test/CodeGen/ARM/cache-intrinsic.ll new file mode 100644 index 00000000000..6048917ee9a --- /dev/null +++ b/test/CodeGen/ARM/cache-intrinsic.ll @@ -0,0 +1,26 @@ +; RUN: llc %s -o - | FileCheck %s +target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-n32-S64" +target triple = "armv7--linux-gnueabihf" + +@buffer = global [32 x i8] c"This is a largely unused buffer\00", align 1 +@.str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1 +@.str1 = private unnamed_addr constant [25 x i8] c"Still, largely unused...\00", align 1 + +define i32 @main() { +entry: + %retval = alloca i32, align 4 + store i32 0, i32* %retval + %call = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([4 x i8]* @.str, i32 0, i32 0), i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0)) + %call1 = call i8* @strcpy(i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0), i8* getelementptr inbounds ([25 x i8]* @.str1, i32 0, i32 0)) #3 + call void @llvm.clear_cache(i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0), i8* getelementptr inbounds (i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0), i32 32)) #3 + %call2 = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([4 x i8]* @.str, i32 0, i32 0), i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0)) + ret i32 0 +} + +; CHECK: __clear_cache + +declare i32 @printf(i8*, ...) + +declare i8* @strcpy(i8*, i8*) + +declare void @llvm.clear_cache(i8*, i8*) diff --git a/test/CodeGen/Mips/cache-intrinsic.ll b/test/CodeGen/Mips/cache-intrinsic.ll new file mode 100644 index 00000000000..2fa41158959 --- /dev/null +++ b/test/CodeGen/Mips/cache-intrinsic.ll @@ -0,0 +1,26 @@ +; RUN: llc %s -o - | FileCheck %s +target datalayout = "E-p:32:32:32-i1:8:8-i8:8:32-i16:16:32-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-n32-S64" +target triple = "mips--linux-gnu" + +@buffer = global [32 x i8] c"This is a largely unused buffer\00", align 1 +@.str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1 +@.str1 = private unnamed_addr constant [25 x i8] c"Still, largely unused...\00", align 1 + +define i32 @main() { +entry: + %retval = alloca i32, align 4 + store i32 0, i32* %retval + %call = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([4 x i8]* @.str, i32 0, i32 0), i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0)) + %call1 = call i8* @strcpy(i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0), i8* getelementptr inbounds ([25 x i8]* @.str1, i32 0, i32 0)) #3 + call void @llvm.clear_cache(i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0), i8* getelementptr inbounds (i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0), i32 32)) #3 + %call2 = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([4 x i8]* @.str, i32 0, i32 0), i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0)) + ret i32 0 +} + +; CHECK: __clear_cache + +declare i32 @printf(i8*, ...) + +declare i8* @strcpy(i8*, i8*) + +declare void @llvm.clear_cache(i8*, i8*) diff --git a/test/CodeGen/X86/cache-intrinsic.ll b/test/CodeGen/X86/cache-intrinsic.ll new file mode 100644 index 00000000000..3091b5ff311 --- /dev/null +++ b/test/CodeGen/X86/cache-intrinsic.ll @@ -0,0 +1,26 @@ +; RUN: llc %s -o - | FileCheck %s +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +@buffer = global [32 x i8] c"This is a largely unused buffer\00", align 16 +@.str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1 +@.str1 = private unnamed_addr constant [25 x i8] c"Still, largely unused...\00", align 1 + +define i32 @main() { +entry: + %retval = alloca i32, align 4 + store i32 0, i32* %retval + %call = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([4 x i8]* @.str, i32 0, i32 0), i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0)) + %call1 = call i8* @strcpy(i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0), i8* getelementptr inbounds ([25 x i8]* @.str1, i32 0, i32 0)) #3 + call void @llvm.clear_cache(i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0), i8* getelementptr inbounds (i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0), i32 32)) #3 + %call3 = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([4 x i8]* @.str, i32 0, i32 0), i8* getelementptr inbounds ([32 x i8]* @buffer, i32 0, i32 0)) + ret i32 0 +} + +; CHECK-NOT: __clear_cache + +declare i32 @printf(i8*, ...) + +declare i8* @strcpy(i8*, i8*) + +declare void @llvm.clear_cache(i8*, i8*)