[clang] a4f84f1 - [CodeGen] Track DeferredDecls that have been emitted

[Jun Zhang via cfe-commits]

Author: Jun Zhang
Date: 2022-08-27T22:32:47+08:00
New Revision: a4f84f1b2e92ea79b70b9961049a1af7d9e1f2fa

URL: https://github.com/llvm/llvm-project/commit/a4f84f1b2e92ea79b70b9961049a1af7d9e1f2fa
DIFF: https://github.com/llvm/llvm-project/commit/a4f84f1b2e92ea79b70b9961049a1af7d9e1f2fa.diff

LOG: [CodeGen] Track DeferredDecls that have been emitted

If we run into a first usage or definition of a mangled name, and
there's a DeferredDecl that associated with it, we should remember it we
need to emit it later on.

Without this patch, clang-repl hits a JIT symbol not found error:
clang-repl> extern "C" int printf(const char *, ...);
clang-repl> auto l1 = []() { printf("ONE\n"); return 42; };
clang-repl> auto l2 = []() { printf("TWO\n"); return 17; };
clang-repl> auto r1 = l1();
ONE
clang-repl> auto r2 = l2();
TWO
clang-repl> auto r3 = l2();
JIT session error: Symbols not found: [ l2 ]
error: Failed to materialize symbols: { (main,
{ r3, orc_init_func.incr_module_5, $.incr_module_5.inits.0 }) }

Signed-off-by: Jun Zhang <jun at junz.org>

Differential Revision: https://reviews.llvm.org/D130831

Added: 
    clang/test/Interpreter/lambda.cpp

Modified: 
    clang/lib/CodeGen/CodeGenModule.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 2ced1c5419813..6294fe9e87d32 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -3356,6 +3356,7 @@ void CodeGenModule::EmitGlobal(GlobalDecl GD) {
     // The value must be emitted, but cannot be emitted eagerly.
     assert(!MayBeEmittedEagerly(Global));
     addDeferredDeclToEmit(GD);
+    EmittedDeferredDecls[MangledName] = GD;
   } else {
     // Otherwise, remember that we saw a deferred decl with this name.  The
     // first use of the mangled name will cause it to move into
@@ -4073,6 +4074,7 @@ llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction(
       // DeferredDeclsToEmit list, and remove it from DeferredDecls (since we
       // don't need it anymore).
       addDeferredDeclToEmit(DDI->second);
+      EmittedDeferredDecls[DDI->first] = DDI->second;
       DeferredDecls.erase(DDI);
 
       // Otherwise, there are cases we have to worry about where we're
@@ -4354,6 +4356,7 @@ CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty,
     // Move the potentially referenced deferred decl to the DeferredDeclsToEmit
     // list, and remove it from DeferredDecls (since we don't need it anymore).
     addDeferredDeclToEmit(DDI->second);
+    EmittedDeferredDecls[DDI->first] = DDI->second;
     DeferredDecls.erase(DDI);
   }
 

diff  --git a/clang/test/Interpreter/lambda.cpp b/clang/test/Interpreter/lambda.cpp
new file mode 100644
index 0000000000000..d06009d59fe08
--- /dev/null
+++ b/clang/test/Interpreter/lambda.cpp
@@ -0,0 +1,21 @@
+// RUN: clang-repl "int x = 10;" "int y=7; err;" "int y = 10;"
+// RUN: clang-repl "int i = 10;" 'extern "C" int printf(const char*,...);' \
+// RUN:            'auto r1 = printf("i = %d\n", i);' | FileCheck --check-prefix=CHECK-DRIVER %s
+// REQUIRES: host-supports-jit
+// UNSUPPORTED: system-aix
+// CHECK-DRIVER: i = 10
+// RUN: cat %s | clang-repl | FileCheck %s
+// RUN: cat %s | clang-repl -Xcc -O2 | FileCheck %s
+extern "C" int printf(const char *, ...);
+
+auto l1 = []() { printf("ONE\n"); return 42; };
+auto l2 = []() { printf("TWO\n"); return 17; };
+
+auto r1 = l1();
+// CHECK: ONE
+auto r2 = l2();
+// CHECK: TWO
+auto r3 = l2();
+// CHECK: TWO
+
+%quit