[CodeGen] Improve diagnostics related to target attributes
Summary:
When requirement imposed by __target__ attributes on functions
are not satisfied, prefer printing those requirements, which
are explicitly mentioned in the attributes.
This makes such messages more useful, e.g. printing avx512f instead of avx2
in the following scenario:
```
$ cat foo.c
static inline void __attribute__((__always_inline__, __target__("avx512f")))
x(void)
{
}
int main(void)
{
x();
}
$ clang foo.c
foo.c:7:2: error: always_inline function 'x' requires target feature 'avx2', but would be inlined into function 'main' that is compiled without support for 'avx2'
x();
^
1 error generated.
```
bugzilla: https://bugs.llvm.org/show_bug.cgi?id=37338
Reviewers: craig.topper, echristo, dblaikie
Reviewed By: craig.topper, echristo
Differential Revision: https://reviews.llvm.org/D46541
llvm-svn: 334174
diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index 6c73a8c..9160515 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -2330,9 +2330,19 @@
} else if (TargetDecl->hasAttr<TargetAttr>()) {
// Get the required features for the callee.
+
+ const TargetAttr *TD = TargetDecl->getAttr<TargetAttr>();
+ TargetAttr::ParsedTargetAttr ParsedAttr = CGM.filterFunctionTargetAttrs(TD);
+
SmallVector<StringRef, 1> ReqFeatures;
llvm::StringMap<bool> CalleeFeatureMap;
CGM.getFunctionFeatureMap(CalleeFeatureMap, TargetDecl);
+
+ for (const auto &F : ParsedAttr.Features) {
+ if (F[0] == '+' && CalleeFeatureMap.lookup(F.substr(1)))
+ ReqFeatures.push_back(StringRef(F).substr(1));
+ }
+
for (const auto &F : CalleeFeatureMap) {
// Only positive features are "required".
if (F.getValue())
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index b57004f..19cfffd 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -5033,22 +5033,28 @@
}
}
+TargetAttr::ParsedTargetAttr CodeGenModule::filterFunctionTargetAttrs(const TargetAttr *TD) {
+ assert(TD != nullptr);
+ TargetAttr::ParsedTargetAttr ParsedAttr = TD->parse();
+
+ ParsedAttr.Features.erase(
+ llvm::remove_if(ParsedAttr.Features,
+ [&](const std::string &Feat) {
+ return !Target.isValidFeatureName(
+ StringRef{Feat}.substr(1));
+ }),
+ ParsedAttr.Features.end());
+ return ParsedAttr;
+}
+
+
// Fills in the supplied string map with the set of target features for the
// passed in function.
void CodeGenModule::getFunctionFeatureMap(llvm::StringMap<bool> &FeatureMap,
const FunctionDecl *FD) {
StringRef TargetCPU = Target.getTargetOpts().CPU;
if (const auto *TD = FD->getAttr<TargetAttr>()) {
- // If we have a TargetAttr build up the feature map based on that.
- TargetAttr::ParsedTargetAttr ParsedAttr = TD->parse();
-
- ParsedAttr.Features.erase(
- llvm::remove_if(ParsedAttr.Features,
- [&](const std::string &Feat) {
- return !Target.isValidFeatureName(
- StringRef{Feat}.substr(1));
- }),
- ParsedAttr.Features.end());
+ TargetAttr::ParsedTargetAttr ParsedAttr = filterFunctionTargetAttrs(TD);
// Make a copy of the features as passed on the command line into the
// beginning of the additional features from the function to override.
diff --git a/clang/lib/CodeGen/CodeGenModule.h b/clang/lib/CodeGen/CodeGenModule.h
index 961bae3..8982398 100644
--- a/clang/lib/CodeGen/CodeGenModule.h
+++ b/clang/lib/CodeGen/CodeGenModule.h
@@ -1089,6 +1089,10 @@
/// It's up to you to ensure that this is safe.
void AddDefaultFnAttrs(llvm::Function &F);
+ /// Parses the target attributes passed in, and returns only the ones that are
+ /// valid feature names.
+ TargetAttr::ParsedTargetAttr filterFunctionTargetAttrs(const TargetAttr *TD);
+
// Fills in the supplied string map with the set of target features for the
// passed in function.
void getFunctionFeatureMap(llvm::StringMap<bool> &FeatureMap,