https://github.com/aeubanks updated 
https://github.com/llvm/llvm-project/pull/124834

>From 7c40169ec7430ec64aaeb053e423eca1ceff7f0d Mon Sep 17 00:00:00 2001
From: Arthur Eubanks <aeuba...@google.com>
Date: Tue, 28 Jan 2025 20:36:58 +0000
Subject: [PATCH 1/2] [clang][X86] Support
 __attribute__((model("small"/"large")))

Following up #72078, on x86-64 this allows a global to be considered
small or large regardless of the code model. For example, x86-64's
medium code model by default classifies globals as small or large
depending on their size relative to -mlarge-data-threshold.
---
 clang/docs/ReleaseNotes.rst          |  5 +++++
 clang/include/clang/Basic/Attr.td    | 13 +++++++++----
 clang/lib/Sema/SemaDeclAttr.cpp      | 11 ++++++++++-
 clang/test/CodeGen/X86/codemodel.cpp | 27 +++++++++++++++++++++++++++
 clang/test/Sema/attr-model.cpp       | 22 ++++++++++------------
 5 files changed, 61 insertions(+), 17 deletions(-)
 create mode 100644 clang/test/CodeGen/X86/codemodel.cpp

diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 7b5562a80a35a6..dba3ed593dae28 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -657,6 +657,11 @@ Attribute Changes in Clang
 
 - Clang now disallows the use of attributes after the namespace name. 
(#GH121407)
 
+- Clang now allows ``__attribute__((model("small")))`` and
+  ``__attribute__((model("large")))`` on non-TLS globals in x86-64 
compilations.
+  This forces the global to be considered small or large in regards to the
+  x86-64 code model, regardless of the code model specified for the 
compilation.
+
 Improvements to Clang's diagnostics
 -----------------------------------
 
diff --git a/clang/include/clang/Basic/Attr.td 
b/clang/include/clang/Basic/Attr.td
index f4ba2bc3c6de31..092dc751d79f22 100644
--- a/clang/include/clang/Basic/Attr.td
+++ b/clang/include/clang/Basic/Attr.td
@@ -462,6 +462,7 @@ def TargetMSP430 : TargetArch<["msp430"]>;
 def TargetM68k : TargetArch<["m68k"]>;
 def TargetRISCV : TargetArch<["riscv32", "riscv64"]>;
 def TargetX86 : TargetArch<["x86"]>;
+def TargetX86_64 : TargetArch<["x86_64"]>;
 def TargetAnyX86 : TargetArch<["x86", "x86_64"]>;
 def TargetWebAssembly : TargetArch<["wasm32", "wasm64"]>;
 def TargetNVPTX : TargetArch<["nvptx", "nvptx64"]>;
@@ -3117,11 +3118,15 @@ def PragmaClangTextSection : InheritableAttr {
   let Documentation = [InternalOnly];
 }
 
-def CodeModel : InheritableAttr, TargetSpecificAttr<TargetLoongArch> {
+def CodeModel : InheritableAttr,
+                TargetSpecificAttr<TargetArch<!listconcat(
+                    TargetLoongArch.Arches, TargetX86_64.Arches)>> {
   let Spellings = [GCC<"model">];
-  let Args = [EnumArgument<"Model", "llvm::CodeModel::Model", /*is_string=*/1,
-              ["normal", "medium", "extreme"], ["Small", "Medium", "Large"],
-              /*opt=*/0, /*fake=*/0, /*isExternalType=*/1, /*isCovered=*/0>];
+  let Args = [EnumArgument<
+      "Model", "llvm::CodeModel::Model",
+      /*is_string=*/1, ["small", "normal", "medium", "large", "extreme"],
+      ["Small", "Small", "Medium", "Large", "Large"],
+      /*opt=*/0, /*fake=*/0, /*isExternalType=*/1, /*isCovered=*/0>];
   let Subjects = SubjectList<[NonTLSGlobalVar], ErrorDiag>;
   let Documentation = [CodeModelDocs];
 }
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index 9d7d22590bce4b..e2c752df06c25a 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -64,6 +64,7 @@
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/MC/MCSectionMachO.h"
 #include "llvm/Support/Error.h"
+#include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/TargetParser/Triple.h"
@@ -2949,6 +2950,13 @@ static void handleSectionAttr(Sema &S, Decl *D, const 
ParsedAttr &AL) {
   }
 }
 
+static bool isValidCodeModelAttr(Sema &S, StringRef Str) {
+  bool IsX8664Target =
+      S.Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86_64;
+  bool IsX8664Spelling = Str == "small" || Str == "large";
+  return IsX8664Target == IsX8664Spelling;
+}
+
 static void handleCodeModelAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
   StringRef Str;
   SourceLocation LiteralLoc;
@@ -2957,7 +2965,8 @@ static void handleCodeModelAttr(Sema &S, Decl *D, const 
ParsedAttr &AL) {
     return;
 
   llvm::CodeModel::Model CM;
-  if (!CodeModelAttr::ConvertStrToModel(Str, CM)) {
+  if (!CodeModelAttr::ConvertStrToModel(Str, CM) ||
+      !isValidCodeModelAttr(S, Str)) {
     S.Diag(LiteralLoc, diag::err_attr_codemodel_arg) << Str;
     return;
   }
diff --git a/clang/test/CodeGen/X86/codemodel.cpp 
b/clang/test/CodeGen/X86/codemodel.cpp
new file mode 100644
index 00000000000000..60a840665b49cd
--- /dev/null
+++ b/clang/test/CodeGen/X86/codemodel.cpp
@@ -0,0 +1,27 @@
+// RUN: %clang_cc1 -emit-llvm -triple x86_64-unknown-unknown %s -o - | 
FileCheck %s
+
+// CHECK: @_ZL2v1 ={{.*}} global i32 0, code_model "small"
+static int v1 __attribute__((model("small")));
+
+void use1() {
+  v1 = 1;
+}
+
+// CHECK: @v2 ={{.*}} global float 0.000000e+00, code_model "large"
+float v2 __attribute__((model("large")));
+
+// CHECK: @_ZL2v3IiE ={{.*}} global i32 0, code_model "small"
+template <typename T>
+static T v3 __attribute__((model("small")));
+
+void use2() {
+  v3<int> = 1;
+}
+struct S {
+  double d;
+};
+
+typedef void (*F)();
+
+// CHECK: @v4 ={{.*}} global ptr null, code_model "large"
+F v4 __attribute__((model("large")));
diff --git a/clang/test/Sema/attr-model.cpp b/clang/test/Sema/attr-model.cpp
index 898cc039398436..725ec502df3962 100644
--- a/clang/test/Sema/attr-model.cpp
+++ b/clang/test/Sema/attr-model.cpp
@@ -5,7 +5,7 @@
 // RUN: %clang_cc1 -triple riscv64 -verify=expected,riscv64 -fsyntax-only %s
 // RUN: %clang_cc1 -triple x86_64 -verify=expected,x86_64 -fsyntax-only %s
 
-#if defined(__loongarch__) && !__has_attribute(model)
+#if (defined(__loongarch__) || defined(__x86_64__)) && !__has_attribute(model)
 #error "Should support model attribute"
 #endif
 
@@ -14,51 +14,49 @@ int a __attribute((model("tiny")));    // aarch64-warning 
{{unknown attribute 'm
                                        // mips64-warning {{unknown attribute 
'model' ignored}} \
                                        // powerpc64-warning {{unknown 
attribute 'model' ignored}} \
                                        // riscv64-warning {{unknown attribute 
'model' ignored}} \
-                                       // x86_64-warning {{unknown attribute 
'model' ignored}}
+                                       // x86_64-error {{code model 'tiny' is 
not supported on this target}}
 int b __attribute((model("small")));   // aarch64-warning {{unknown attribute 
'model' ignored}} \
                                        // loongarch64-error {{code model 
'small' is not supported on this target}} \
                                        // mips64-warning {{unknown attribute 
'model' ignored}} \
                                        // powerpc64-warning {{unknown 
attribute 'model' ignored}} \
-                                       // riscv64-warning {{unknown attribute 
'model' ignored}} \
-                                       // x86_64-warning {{unknown attribute 
'model' ignored}}
+                                       // riscv64-warning {{unknown attribute 
'model' ignored}}
 int c __attribute((model("normal")));  // aarch64-warning {{unknown attribute 
'model' ignored}} \
                                        // mips64-warning {{unknown attribute 
'model' ignored}} \
                                        // powerpc64-warning {{unknown 
attribute 'model' ignored}} \
                                        // riscv64-warning {{unknown attribute 
'model' ignored}} \
-                                       // x86_64-warning {{unknown attribute 
'model' ignored}}
+                                       // x86_64-error {{code model 'normal' 
is not supported on this target}}
 int d __attribute((model("kernel")));  // aarch64-warning {{unknown attribute 
'model' ignored}} \
                                        // loongarch64-error {{code model 
'kernel' is not supported on this target}} \
                                        // mips64-warning {{unknown attribute 
'model' ignored}} \
                                        // powerpc64-warning {{unknown 
attribute 'model' ignored}} \
                                        // riscv64-warning {{unknown attribute 
'model' ignored}} \
-                                       // x86_64-warning {{unknown attribute 
'model' ignored}}
+                                       // x86_64-error {{code model 'kernel' 
is not supported on this target}}
 int e __attribute((model("medium")));  // aarch64-warning {{unknown attribute 
'model' ignored}} \
                                        // mips64-warning {{unknown attribute 
'model' ignored}} \
                                        // powerpc64-warning {{unknown 
attribute 'model' ignored}} \
                                        // riscv64-warning {{unknown attribute 
'model' ignored}} \
-                                       // x86_64-warning {{unknown attribute 
'model' ignored}}
+                                       // x86_64-error {{code model 'medium' 
is not supported on this target}}
 int f __attribute((model("large")));   // aarch64-warning {{unknown attribute 
'model' ignored}} \
                                        // loongarch64-error {{code model 
'large' is not supported on this target}} \
                                        // mips64-warning {{unknown attribute 
'model' ignored}} \
                                        // powerpc64-warning {{unknown 
attribute 'model' ignored}} \
-                                       // riscv64-warning {{unknown attribute 
'model' ignored}} \
-                                       // x86_64-warning {{unknown attribute 
'model' ignored}}
+                                       // riscv64-warning {{unknown attribute 
'model' ignored}}
 int g __attribute((model("extreme"))); // aarch64-warning {{unknown attribute 
'model' ignored}} \
                                        // mips64-warning {{unknown attribute 
'model' ignored}} \
                                        // powerpc64-warning {{unknown 
attribute 'model' ignored}} \
                                        // riscv64-warning {{unknown attribute 
'model' ignored}} \
-                                       // x86_64-warning {{unknown attribute 
'model' ignored}}
+                                       // x86_64-error {{code model 'extreme' 
is not supported on this target}}
 
 void __attribute((model("extreme"))) h() {} // aarch64-warning {{unknown 
attribute 'model' ignored}} \
                                             // loongarch64-error {{'model' 
attribute only applies to non-TLS global variables}} \
                                             // mips64-warning {{unknown 
attribute 'model' ignored}} \
                                             // powerpc64-warning {{unknown 
attribute 'model' ignored}} \
                                             // riscv64-warning {{unknown 
attribute 'model' ignored}} \
-                                            // x86_64-warning {{unknown 
attribute 'model' ignored}}
+                                            // x86_64-error {{'model' 
attribute only applies to non-TLS global variables}}
 
 thread_local int i __attribute((model("extreme"))); // aarch64-warning 
{{unknown attribute 'model' ignored}} \
                                                     // loongarch64-error 
{{'model' attribute only applies to non-TLS global variables}} \
                                                     // mips64-warning 
{{unknown attribute 'model' ignored}} \
                                                     // powerpc64-warning 
{{unknown attribute 'model' ignored}} \
                                                     // riscv64-warning 
{{unknown attribute 'model' ignored}} \
-                                                    // x86_64-warning 
{{unknown attribute 'model' ignored}}
+                                                    // x86_64-error {{'model' 
attribute only applies to non-TLS global variables}}

>From 8aa6b3fd3a7c33b80e598fc13b08aafcf6eae66e Mon Sep 17 00:00:00 2001
From: Arthur Eubanks <aeuba...@google.com>
Date: Wed, 29 Jan 2025 19:32:27 +0000
Subject: [PATCH 2/2] address comments

---
 clang/lib/Sema/SemaDeclAttr.cpp | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index e2c752df06c25a..bb69d3226eb419 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -2951,10 +2951,14 @@ static void handleSectionAttr(Sema &S, Decl *D, const 
ParsedAttr &AL) {
 }
 
 static bool isValidCodeModelAttr(Sema &S, StringRef Str) {
-  bool IsX8664Target =
-      S.Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86_64;
-  bool IsX8664Spelling = Str == "small" || Str == "large";
-  return IsX8664Target == IsX8664Spelling;
+  if (S.Context.getTargetInfo().getTriple().isLoongArch()) {
+    return Str == "normal" || Str == "medium" || Str == "extreme";
+  } else {
+    assert(S.Context.getTargetInfo().getTriple().getArch() ==
+               llvm::Triple::x86_64 &&
+           "only loongarch/x86-64 supported");
+    return Str == "small" || Str == "large";
+  }
 }
 
 static void handleCodeModelAttr(Sema &S, Decl *D, const ParsedAttr &AL) {

_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits

Reply via email to