[clang] e9644e6 - DebugInfo: Fix default template parameter computation for dependent non-type template parameters

[David Blaikie via cfe-commits]

Author: David Blaikie
Date: 2020-04-05T16:31:30-07:00
New Revision: e9644e6f4f21e6b6177ef9085cdc9ed9f44b7783

URL: https://github.com/llvm/llvm-project/commit/e9644e6f4f21e6b6177ef9085cdc9ed9f44b7783
DIFF: https://github.com/llvm/llvm-project/commit/e9644e6f4f21e6b6177ef9085cdc9ed9f44b7783.diff

LOG: DebugInfo: Fix default template parameter computation for dependent non-type template parameters

This addresses the immediate bug, though in theory we could still
produce a default parameter for the DWARF in this test case - but other
cases will be definitely unachievable (you could have a default
parameter that cannot be evaluated - so long as the user overrode it
with another value rather than relying on that default)

Added: 
    

Modified: 
    clang/lib/CodeGen/CGDebugInfo.cpp
    clang/test/CodeGenCXX/debug-info-template-parameter.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 6d3c2ad66cdc..5f05323f61ef 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -1816,7 +1816,8 @@ CGDebugInfo::CollectTemplateParams(const TemplateParameterList *TPList,
       if (TPList && CGM.getCodeGenOpts().DwarfVersion >= 5)
         if (auto *templateType =
                 dyn_cast_or_null<NonTypeTemplateParmDecl>(TPList->getParam(i)))
-          if (templateType->hasDefaultArgument())
+          if (templateType->hasDefaultArgument() &&
+              !templateType->getDefaultArgument()->isValueDependent())
             defaultParameter = llvm::APSInt::isSameValue(
                 templateType->getDefaultArgument()->EvaluateKnownConstInt(
                     CGM.getContext()),

diff  --git a/clang/test/CodeGenCXX/debug-info-template-parameter.cpp b/clang/test/CodeGenCXX/debug-info-template-parameter.cpp
index c38c535d8b06..fee6dfe8b898 100644
--- a/clang/test/CodeGenCXX/debug-info-template-parameter.cpp
+++ b/clang/test/CodeGenCXX/debug-info-template-parameter.cpp
@@ -8,24 +8,24 @@
 
 // CHECK: DILocalVariable(name: "f1", {{.*}}, type: ![[TEMPLATE_TYPE:[0-9]+]]
 // CHECK: [[TEMPLATE_TYPE]] = {{.*}}!DICompositeType({{.*}}, templateParams: ![[F1_TYPE:[0-9]+]]
-// CHECK: [[F1_TYPE]] = !{![[FIRST:[0-9]+]], ![[SECOND:[0-9]+]], ![[THIRD:[0-9]+]]}
+// CHECK: [[F1_TYPE]] = !{![[FIRST:[0-9]+]], ![[SECOND:[0-9]+]], ![[THIRD:[0-9]+]], ![[FORTH:[0-9]+]]}
 // CHECK: [[FIRST]] = !DITemplateTypeParameter(name: "T", type: !{{[0-9]*}})
 // CHECK: [[SECOND]] = !DITemplateValueParameter(name: "i", type: !{{[0-9]*}}, value: i32 6)
 // CHECK: [[THIRD]] = !DITemplateValueParameter(name: "b", type: !{{[0-9]*}}, value: i8 0)
 
 // CHECK: DILocalVariable(name: "f2", {{.*}}, type: ![[TEMPLATE_TYPE:[0-9]+]]
 // CHECK: [[TEMPLATE_TYPE]] = {{.*}}!DICompositeType({{.*}}, templateParams: ![[F2_TYPE:[0-9]+]]
-// CHECK: [[F2_TYPE]] = !{![[FIRST:[0-9]+]], ![[SECOND:[0-9]+]], ![[THIRD:[0-9]+]]}
+// CHECK: [[F2_TYPE]] = !{![[FIRST:[0-9]+]], ![[SECOND:[0-9]+]], ![[THIRD:[0-9]+]], ![[FORTH:[0-9]+]]}
 // CHECK: [[FIRST]] = !DITemplateTypeParameter(name: "T", type: !{{[0-9]*}}, defaulted: true)
 // CHECK: [[SECOND]] = !DITemplateValueParameter(name: "i", type: !{{[0-9]*}}, defaulted: true, value: i32 3)
 // CHECK: [[THIRD]] = !DITemplateValueParameter(name: "b", type: !{{[0-9]*}}, defaulted: true, value: i8 1)
 
-template <typename T = char, int i = 3, bool b = true>
+template <typename T = char, int i = 3, bool b = true, int x = sizeof(T)>
 class foo {
 };
 
 int main() {
-  foo<int, 6, false> f1;
+  foo<int, 6, false, 3> f1;
   foo<> f2;
   return 0;
 }