Author: Kees Cook Date: 2024-04-29T14:54:10-07:00 New Revision: 869ffcf3f6ca74c8a0ec6eb250d45e6ea0680c81
URL: https://github.com/llvm/llvm-project/commit/869ffcf3f6ca74c8a0ec6eb250d45e6ea0680c81 DIFF: https://github.com/llvm/llvm-project/commit/869ffcf3f6ca74c8a0ec6eb250d45e6ea0680c81.diff LOG: [CodeGen][i386] Move -mregparm storage earlier and fix Runtime calls (#89707) When building the Linux kernel for i386, the -mregparm=3 option is enabled. Crashes were observed in the sanitizer handler functions, and the problem was found to be mismatched calling convention. As was fixed in commit c167c0a4dcdb ("[BuildLibCalls] infer inreg param attrs from NumRegisterParameters"), call arguments need to be marked as "in register" when -mregparm is set. Use the same helper developed there to update the function arguments. Since CreateRuntimeFunction() is actually part of CodeGenModule, storage of the -mregparm value is also moved to the constructor, as doing this in Release() is too late. Fixes: https://github.com/llvm/llvm-project/issues/89670 Added: Modified: clang/lib/CodeGen/CodeGenModule.cpp clang/test/CodeGen/regparm-flag.c llvm/include/llvm/Transforms/Utils/BuildLibCalls.h llvm/lib/Transforms/Utils/BuildLibCalls.cpp Removed: ################################################################################ diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp index d085e735ecb443..c8898ce196c1ed 100644 --- a/clang/lib/CodeGen/CodeGenModule.cpp +++ b/clang/lib/CodeGen/CodeGenModule.cpp @@ -73,6 +73,7 @@ #include "llvm/TargetParser/RISCVISAInfo.h" #include "llvm/TargetParser/Triple.h" #include "llvm/TargetParser/X86TargetParser.h" +#include "llvm/Transforms/Utils/BuildLibCalls.h" #include <optional> using namespace clang; @@ -442,6 +443,11 @@ CodeGenModule::CodeGenModule(ASTContext &C, } ModuleNameHash = llvm::getUniqueInternalLinkagePostfix(Path); } + + // Record mregparm value now so it is visible through all of codegen. + if (Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86) + getModule().addModuleFlag(llvm::Module::Error, "NumRegisterParameters", + CodeGenOpts.NumRegisterParameters); } CodeGenModule::~CodeGenModule() {} @@ -980,11 +986,6 @@ void CodeGenModule::Release() { NMD->addOperand(MD); } - // Record mregparm value now so it is visible through rest of codegen. - if (Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86) - getModule().addModuleFlag(llvm::Module::Error, "NumRegisterParameters", - CodeGenOpts.NumRegisterParameters); - if (CodeGenOpts.DwarfVersion) { getModule().addModuleFlag(llvm::Module::Max, "Dwarf Version", CodeGenOpts.DwarfVersion); @@ -4781,6 +4782,10 @@ CodeGenModule::CreateRuntimeFunction(llvm::FunctionType *FTy, StringRef Name, } } setDSOLocal(F); + // FIXME: We should use CodeGenModule::SetLLVMFunctionAttributes() instead + // of trying to approximate the attributes using the LLVM function + // signature. This requires revising the API of CreateRuntimeFunction(). + markRegisterParameterAttributes(F); } } diff --git a/clang/test/CodeGen/regparm-flag.c b/clang/test/CodeGen/regparm-flag.c index c35b53cd4e1990..d888c1e344c03b 100644 --- a/clang/test/CodeGen/regparm-flag.c +++ b/clang/test/CodeGen/regparm-flag.c @@ -1,4 +1,8 @@ // RUN: %clang_cc1 -triple i386-unknown-unknown -mregparm 4 %s -emit-llvm -o - | FileCheck %s +// RUN: %clang_cc1 -triple i386-unknown-unknown -fsanitize=array-bounds %s -emit-llvm -o - | FileCheck %s --check-prefix=RUNTIME0 +// RUN: %clang_cc1 -triple i386-unknown-unknown -mregparm 1 -fsanitize=array-bounds %s -emit-llvm -o - | FileCheck %s --check-prefix=RUNTIME1 +// RUN: %clang_cc1 -triple i386-unknown-unknown -mregparm 2 -fsanitize=array-bounds %s -emit-llvm -o - | FileCheck %s --check-prefix=RUNTIME2 +// RUN: %clang_cc1 -triple i386-unknown-unknown -mregparm 3 -fsanitize=array-bounds %s -emit-llvm -o - | FileCheck %s --check-prefix=RUNTIME2 void f1(int a, int b, int c, int d, int e, int f, int g, int h); @@ -13,7 +17,21 @@ void f0(void) { f2(1, 2); } +struct has_array { + int a; + int b[4]; + int c; +}; + +int access(struct has_array *p, int index) +{ + return p->b[index]; +} + // CHECK: declare void @f1(i32 inreg noundef, i32 inreg noundef, i32 inreg noundef, i32 inreg noundef, // CHECK: i32 noundef, i32 noundef, i32 noundef, i32 noundef) // CHECK: declare void @f2(i32 noundef, i32 noundef) +// RUNTIME0: declare void @__ubsan_handle_out_of_bounds_abort(ptr, i32) +// RUNTIME1: declare void @__ubsan_handle_out_of_bounds_abort(ptr inreg, i32) +// RUNTIME2: declare void @__ubsan_handle_out_of_bounds_abort(ptr inreg, i32 inreg) diff --git a/llvm/include/llvm/Transforms/Utils/BuildLibCalls.h b/llvm/include/llvm/Transforms/Utils/BuildLibCalls.h index 9ebb9500777421..429d6a2e05236f 100644 --- a/llvm/include/llvm/Transforms/Utils/BuildLibCalls.h +++ b/llvm/include/llvm/Transforms/Utils/BuildLibCalls.h @@ -62,6 +62,13 @@ namespace llvm { LibFunc TheLibFunc, AttributeList AttributeList, FunctionType *Invalid, ArgsTy... Args) = delete; + // Handle -mregparm for the given function. + // Note that this function is a rough approximation that only works for simple + // function signatures; it does not apply other relevant attributes for + // function signatures, including sign/zero-extension for arguments and return + // values. + void markRegisterParameterAttributes(Function *F); + /// Check whether the library function is available on target and also that /// it in the current Module is a Function with the right type. bool isLibFuncEmittable(const Module *M, const TargetLibraryInfo *TLI, diff --git a/llvm/lib/Transforms/Utils/BuildLibCalls.cpp b/llvm/lib/Transforms/Utils/BuildLibCalls.cpp index ed0ed345435c45..e97506b4bbd95d 100644 --- a/llvm/lib/Transforms/Utils/BuildLibCalls.cpp +++ b/llvm/lib/Transforms/Utils/BuildLibCalls.cpp @@ -1255,7 +1255,7 @@ static void setRetExtAttr(Function &F, } // Modeled after X86TargetLowering::markLibCallAttributes. -static void markRegisterParameterAttributes(Function *F) { +void llvm::markRegisterParameterAttributes(Function *F) { if (!F->arg_size() || F->isVarArg()) return; _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
