[PATCH] D143479: [Clang] Emit error when caller cannot meet target feature requirement from always-inlining callee

[Qiu Chaofan via Phabricator via cfe-commits]

qiucf created this revision.
qiucf added reviewers: echristo, LiuChen3, erichkeane, GBuella.
Herald added subscribers: steven.zhang, kbarton, nemanjai.
Herald added a project: All.
qiucf requested review of this revision.
Herald added a project: clang.
Herald added a subscriber: cfe-commits.

Currently clang emits error when both `always_inline` and `target` attributes are on callee, but caller doesn't have some feature:

  // RUN: %clang_cc1 -triple powerpc64le -target-feature -htm
  
  __attribute__((always_inline))
  __attribute__((target("htm")))
  void foo() {}
  
  void bar() { foo(); }
  
  // error: always_inline function 'foo' requires target feature 'htm', but would be inlined into function 'bar' that is compiled without support for 'htm'

But when the `always_inline` attribute is on caller, clang has no diagnose. If any builtin or inline asm really need the feature, backend will crash.

  // RUN: %clang_cc1 -triple powerpc64le -target-feature +htm
  
  __attribute__((always_inline))
  void foo() {
    // No error, but uncommenting line below triggers ICE
    // __builtin_ttest();
  }
  
  __attribute__((target("no-htm")))
  void bar() { foo(); }

This patch will fix the second case.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D143479

Files:
  clang/lib/CodeGen/CGCall.cpp
  clang/lib/CodeGen/CodeGenFunction.cpp
  clang/test/Sema/ppc-attr-target-inline.c


Index: clang/test/Sema/ppc-attr-target-inline.c
===================================================================
--- /dev/null
+++ clang/test/Sema/ppc-attr-target-inline.c
@@ -0,0 +1,14 @@
+// REQUIRES: powerpc-registered-target
+// RUN: %clang_cc1 -triple powerpc64le -target-feature +htm -fsyntax-only -emit-llvm %s -verify
+
+__attribute__((always_inline))
+int test1(int *x) {
+  *x = __builtin_ttest();
+  return *x;
+}
+
+__attribute__((target("no-htm")))
+int test2(int *x) {
+  *x = test1(x); // expected-error {{always_inline function 'test1' requires target feature 'htm', but would be inlined into function 'test2' that is compiled without support for 'htm'}}
+  return 0;
+}
Index: clang/lib/CodeGen/CodeGenFunction.cpp
===================================================================
--- clang/lib/CodeGen/CodeGenFunction.cpp
+++ clang/lib/CodeGen/CodeGenFunction.cpp
@@ -2611,6 +2611,16 @@
     }))
       CGM.getDiags().Report(Loc, diag::err_function_needs_feature)
           << FD->getDeclName() << TargetDecl->getDeclName() << MissingFeature;
+  } else if (!FD->isMultiVersion() && FD->hasAttr<TargetAttr>()) {
+    llvm::StringMap<bool> CalleeFeatureMap;
+    CGM.getContext().getFunctionFeatureMap(CalleeFeatureMap, TargetDecl);
+
+    for (const auto &F : CalleeFeatureMap) {
+      if (F.getValue() && (!CallerFeatureMap.lookup(F.getKey()) ||
+                           !CallerFeatureMap.find(F.getKey())->getValue()))
+        CGM.getDiags().Report(Loc, diag::err_function_needs_feature)
+            << FD->getDeclName() << TargetDecl->getDeclName() << F.getKey();
+    }
   }
 }
 
Index: clang/lib/CodeGen/CGCall.cpp
===================================================================
--- clang/lib/CodeGen/CGCall.cpp
+++ clang/lib/CodeGen/CGCall.cpp
@@ -4761,7 +4761,8 @@
     // the proper cpu features (and it won't cause code generation issues due to
     // function based code generation).
     if (TargetDecl->hasAttr<AlwaysInlineAttr>() &&
-        TargetDecl->hasAttr<TargetAttr>())
+        (TargetDecl->hasAttr<TargetAttr>() ||
+         (CurFuncDecl && CurFuncDecl->hasAttr<TargetAttr>())))
       checkTargetFeatures(Loc, FD);
 
     // Some architectures (such as x86-64) have the ABI changed based on


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D143479.495426.patch
Type: text/x-patch
Size: 2248 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20230207/e4c96875/attachment.bin>