[clang] 7f2db99 - [PATCH] #pragma float_control should be permitted in namespace scope.

[Melanie Blower via cfe-commits]

Author: Melanie Blower
Date: 2020-05-12T06:10:19-07:00
New Revision: 7f2db993500923a51c0b0aed650a3e0d4241205b

URL: https://github.com/llvm/llvm-project/commit/7f2db993500923a51c0b0aed650a3e0d4241205b
DIFF: https://github.com/llvm/llvm-project/commit/7f2db993500923a51c0b0aed650a3e0d4241205b.diff

LOG: [PATCH] #pragma float_control should be permitted in namespace scope.

Summary: Erroneous error diagnostic observed in VS2017 <numeric> header
Also correction to propagate usesFPIntrin from template func to instantiation.

Reviewers: rjmccall, erichkeane (no feedback received)

Differential Revision: https://reviews.llvm.org/D79631

Added: 
    

Modified: 
    clang/include/clang/Basic/DiagnosticSemaKinds.td
    clang/lib/Sema/SemaAttr.cpp
    clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
    clang/test/CodeGen/fp-floatcontrol-pragma.cpp
    clang/test/Parser/fp-floatcontrol-syntax.cpp

Removed: 
    


################################################################################
diff  --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index 44a34080b239..371e20183e1e 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -860,7 +860,7 @@ def warn_pragma_pack_pop_identifier_and_alignment : Warning<
 def warn_pragma_pop_failed : Warning<"#pragma %0(pop, ...) failed: %1">,
   InGroup<IgnoredPragmas>;
 def err_pragma_fc_pp_scope : Error<
-  "'#pragma float_control push/pop' can only appear at file scope">;
+  "'#pragma float_control push/pop' can only appear at file scope or namespace scope">;
 def err_pragma_fc_noprecise_requires_nofenv : Error<
   "'#pragma float_control(precise, off)' is illegal when fenv_access is enabled">;
 def err_pragma_fc_except_requires_precise : Error<

diff  --git a/clang/lib/Sema/SemaAttr.cpp b/clang/lib/Sema/SemaAttr.cpp
index 01f30a985935..222aaf3049ae 100644
--- a/clang/lib/Sema/SemaAttr.cpp
+++ b/clang/lib/Sema/SemaAttr.cpp
@@ -420,8 +420,8 @@ void Sema::ActOnPragmaFloatControl(SourceLocation Loc,
   auto NewValue = FpPragmaStack.CurrentValue;
   FPOptions NewFPFeatures(NewValue);
   if ((Action == PSK_Push_Set || Action == PSK_Push || Action == PSK_Pop) &&
-      !CurContext->isTranslationUnit()) {
-    // Push and pop can only occur at file scope.
+      !(CurContext->isTranslationUnit()) && !CurContext->isNamespace()) {
+    // Push and pop can only occur at file or namespace scope.
     Diag(Loc, diag::err_pragma_fc_pp_scope);
     return;
   }

diff  --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index a6541dabe6b2..327022218e01 100755
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -1911,6 +1911,7 @@ Decl *TemplateDeclInstantiator::VisitFunctionDecl(
         D->hasWrittenPrototype(), D->getConstexprKind(),
         TrailingRequiresClause);
     Function->setRangeEnd(D->getSourceRange().getEnd());
+    Function->setUsesFPIntrin(D->usesFPIntrin());
   }
 
   if (D->isInlined())

diff  --git a/clang/test/CodeGen/fp-floatcontrol-pragma.cpp b/clang/test/CodeGen/fp-floatcontrol-pragma.cpp
index 773cfcdd2829..a80a4d377660 100644
--- a/clang/test/CodeGen/fp-floatcontrol-pragma.cpp
+++ b/clang/test/CodeGen/fp-floatcontrol-pragma.cpp
@@ -1,3 +1,4 @@
+// RUN: %clang_cc1 -DEXCEPT=1 -fcxx-exceptions -triple x86_64-linux-gnu -emit-llvm -o - %s | FileCheck -check-prefix=CHECK-NS %s
 // RUN: %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -o - %s | FileCheck %s
 // RUN: %clang_cc1 -verify -DFENV_ON=1 -triple x86_64-linux-gnu -emit-llvm -o - %s | FileCheck %s
 
@@ -59,3 +60,56 @@ void callt() {
   z = z * z;
 //CHECK: = fmul float
 }
+
+#if EXCEPT
+namespace ns {
+// Check that pragma float_control can appear in namespace.
+#pragma float_control(except, on, push)
+float exc_on(double x, float zero) {
+// CHECK-NS: define {{.*}}exc_on{{.*}}
+  {} try {
+    x = 1.0 / zero; /* division by zero, the result unused */
+//CHECK-NS: llvm.experimental.constrained.fdiv{{.*}}
+  } catch (...) {}
+  return zero;
+}
+}
+
+// Check pragma is still effective after namespace closes
+float exc_still_on(double x, float zero) {
+// CHECK-NS: define {{.*}}exc_still_on{{.*}}
+  {} try {
+    x = 1.0 / zero; /* division by zero, the result unused */
+//CHECK-NS: llvm.experimental.constrained.fdiv{{.*}}
+  } catch (...) {}
+  return zero;
+}
+
+#pragma float_control(pop)
+float exc_off(double x, float zero) {
+// CHECK-NS: define {{.*}}exc_off{{.*}}
+  {} try {
+    x = 1.0 / zero; /* division by zero, the result unused */
+//CHECK-NS: fdiv contract double
+  } catch (...) {}
+  return zero;
+}
+
+namespace fc_template_namespace {
+#pragma float_control(except, on, push)
+template <class T>
+T exc_on(double x, T zero) {
+// CHECK-NS: define {{.*}}fc_template_namespace{{.*}}
+  {} try {
+    x = 1.0 / zero; /* division by zero, the result unused */
+//CHECK-NS: llvm.experimental.constrained.fdiv{{.*}}
+  } catch (...) {}
+  return zero;
+}
+}
+
+#pragma float_control(pop)
+float xx(double x, float z) {
+  return fc_template_namespace::exc_on<float>(x, z);
+}
+#endif // EXCEPT

diff  --git a/clang/test/Parser/fp-floatcontrol-syntax.cpp b/clang/test/Parser/fp-floatcontrol-syntax.cpp
index 4bdc34dd5ee0..0593c2a0385e 100644
--- a/clang/test/Parser/fp-floatcontrol-syntax.cpp
+++ b/clang/test/Parser/fp-floatcontrol-syntax.cpp
@@ -10,10 +10,10 @@ float function_scope(float a) {
 #pragma float_control(pop)
 #pragma float_control(precise, on, push)
 void check_stack() {
-#pragma float_control(push)                   // expected-error {{can only appear at file scope}}
-#pragma float_control(pop)                    // expected-error {{can only appear at file scope}}
-#pragma float_control(precise, on, push)      // expected-error {{can only appear at file scope}}
-#pragma float_control(except, on, push)       // expected-error {{can only appear at file scope}}
+#pragma float_control(push)                   // expected-error {{can only appear at file scope or namespace scope}}
+#pragma float_control(pop)                    // expected-error {{can only appear at file scope or namespace scope}}
+#pragma float_control(precise, on, push)      // expected-error {{can only appear at file scope or namespace scope}}
+#pragma float_control(except, on, push)       // expected-error {{can only appear at file scope or namespace scope}}
 #pragma float_control(except, on, push, junk) // expected-error {{float_control is malformed}}
   return;
 }