From 610cd8acdd18dd590c452a6846388d210371fdc8 Mon Sep 17 00:00:00 2001
From: Austin Adams <git@austinjadams.com>
Date: Sun, 30 Jun 2024 13:17:59 -0400
Subject: [PATCH 1/2] Add constructor for llvm::Module + entrypoint name

This is useful when a user generates an llvm::Module that may have
multiple entry points, as the Qwerty compiler/runtime does.
---
 src/qiree/Module.cc | 16 ++++++++++++++++
 src/qiree/Module.hh |  3 +++
 2 files changed, 19 insertions(+)

diff --git a/src/qiree/Module.cc b/src/qiree/Module.cc
index 346e311..83d9703 100644
--- a/src/qiree/Module.cc
+++ b/src/qiree/Module.cc
@@ -113,6 +113,22 @@ Module::Module(UPModule&& module) : module_{std::move(module)}
                    << module_->getSourceFileName() << "'");
 }
 
+//---------------------------------------------------------------------------//
+/*!
+ * Construct with an LLVM module and an entry point.
+ */
+Module::Module(UPModule&& module, std::string const& entrypoint)
+    : module_{std::move(module)}
+{
+    QIREE_EXPECT(module_);
+
+    // Search for explicitly named entry point
+    entrypoint_ = module_->getFunction(entrypoint);
+    QIREE_VALIDATE(entrypoint_,
+                   << "no entrypoint function '" << entrypoint << "' exists");
+}
+
+
 //---------------------------------------------------------------------------//
 /*!
  * Construct with an LLVM IR file (bitcode or disassembled).
diff --git a/src/qiree/Module.hh b/src/qiree/Module.hh
index c6ceaed..fc7247c 100644
--- a/src/qiree/Module.hh
+++ b/src/qiree/Module.hh
@@ -45,6 +45,9 @@ class Module
     // Construct from an externally created LLVM module
     explicit Module(UPModule&& module);
 
+    // Construct from an externally created LLVM module and an entry point
+    explicit Module(UPModule&& module, std::string const& entrypoint);
+
     // Construct with an LLVM IR file (bitcode or disassembled)
     explicit Module(std::string const& filename);
 

From 67a113980f8ad71972b80f637ffb851b5055c4da Mon Sep 17 00:00:00 2001
From: Austin Adams <git@austinjadams.com>
Date: Sun, 30 Jun 2024 13:19:39 -0400
Subject: [PATCH 2/2] XaccQuantum: Add setter for accelerator/shots

In my experience, it has been easier to treat XaccQuantum as a singleton
to avoid issues with XACC initializing itself twice.

It is probably cleaner to pass (accelerator, shots) via qiree::Executor,
but this solves my immediate implementaiton problem in the Qwerty
compiler/runtime.
---
 src/qirxacc/XaccQuantum.cc | 15 ++++++++++++---
 src/qirxacc/XaccQuantum.hh |  7 +++++++
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/src/qirxacc/XaccQuantum.cc b/src/qirxacc/XaccQuantum.cc
index 0c5be59..5f97d5e 100644
--- a/src/qirxacc/XaccQuantum.cc
+++ b/src/qirxacc/XaccQuantum.cc
@@ -51,9 +51,7 @@ XaccQuantum::XaccQuantum(std::ostream& os,
     xacc::setIsPyApi();
 
     // Create accelerator
-    accelerator_ = xacc::getAccelerator(accel_name);
-    QIREE_VALIDATE(accelerator_, << "failed to create accelerator");
-    accelerator_->updateConfiguration({{"shots", static_cast<int>(shots)}});
+    set_accelerator_and_shots(accel_name, shots);
     // TODO: bit order is accelerator-dependent?
     endian_ = Endianness::little;
 
@@ -76,6 +74,17 @@ XaccQuantum::~XaccQuantum()
     xacc::Finalize();
 }
 
+//---------------------------------------------------------------------------//
+/*!
+ * Update the XACC accelerator and shot count.
+ */
+void XaccQuantum::set_accelerator_and_shots(
+    std::string const& accel_name, size_type shots) {
+    accelerator_ = xacc::getAccelerator(accel_name);
+    QIREE_VALIDATE(accelerator_, << "failed to create accelerator");
+    accelerator_->updateConfiguration({{"shots", static_cast<int>(shots)}});
+}
+
 //---------------------------------------------------------------------------//
 /*!
  * Prepare to build a quantum circuit for an entry point.
diff --git a/src/qirxacc/XaccQuantum.hh b/src/qirxacc/XaccQuantum.hh
index 3e67cfd..29e143d 100644
--- a/src/qirxacc/XaccQuantum.hh
+++ b/src/qirxacc/XaccQuantum.hh
@@ -58,6 +58,13 @@ class XaccQuantum final : virtual public QuantumNotImpl,
     size_type num_qubits() const { return num_qubits_; }
     //!@}
 
+    //!@{
+    //! \name Mutators
+    // Update the XACC accelerator and shot count
+    void set_accelerator_and_shots(
+        std::string const& accel_name, size_type shots);
+    //!@}
+
     //!@{
     //! \name Quantum interface
     // Prepare to build a quantum circuit for an entry point