Author: Benji Smith
Date: 2024-02-12T10:59:00+01:00
New Revision: b726a81947c40521e047385c5217933c18162187
URL: https://github.com/llvm/llvm-project/commit/b726a81947c40521e047385c5217933c18162187
DIFF: https://github.com/llvm/llvm-project/commit/b726a81947c40521e047385c5217933c18162187.diff
LOG: [C API] Add blockaddress getters to C API (#81382)
This allows for accessing the function/basic block that a blockaddress
constant refers to
Due to the difficulties of fully supporting cloning BlockAddress values
in echo.cpp, tests are instead done using a unit test.
This previously was up for review at
https://github.com/llvm/llvm-project/pull/77390.
Added:
Modified:
llvm/docs/ReleaseNotes.rst
llvm/include/llvm-c/Core.h
llvm/lib/IR/Core.cpp
llvm/unittests/IR/ConstantsTest.cpp
Removed:
################################################################################
diff --git a/llvm/docs/ReleaseNotes.rst b/llvm/docs/ReleaseNotes.rst
index 05d8eea3add419..120e8b637136a6 100644
--- a/llvm/docs/ReleaseNotes.rst
+++ b/llvm/docs/ReleaseNotes.rst
@@ -122,6 +122,9 @@ Changes to the Python bindings
Changes to the C API
--------------------
+* Added ``LLVMGetBlockAddressFunction`` and ``LLVMGetBlockAddressBasicBlock``
+ functions for accessing the values in a blockaddress constant.
+
Changes to the CodeGen infrastructure
-------------------------------------
diff --git a/llvm/include/llvm-c/Core.h b/llvm/include/llvm-c/Core.h
index 83530ae7b51324..09746bdaf0c94e 100644
--- a/llvm/include/llvm-c/Core.h
+++ b/llvm/include/llvm-c/Core.h
@@ -2328,6 +2328,16 @@ LLVMValueRef LLVMConstShuffleVector(LLVMValueRef VectorAConstant,
LLVMValueRef MaskConstant);
LLVMValueRef LLVMBlockAddress(LLVMValueRef F, LLVMBasicBlockRef BB);
+/**
+ * Gets the function associated with a given BlockAddress constant value.
+ */
+LLVMValueRef LLVMGetBlockAddressFunction(LLVMValueRef BlockAddr);
+
+/**
+ * Gets the basic block associated with a given BlockAddress constant value.
+ */
+LLVMBasicBlockRef LLVMGetBlockAddressBasicBlock(LLVMValueRef BlockAddr);
+
/** Deprecated: Use LLVMGetInlineAsm instead. */
LLVMValueRef LLVMConstInlineAsm(LLVMTypeRef Ty,
const char *AsmString, const char *Constraints,
diff --git a/llvm/lib/IR/Core.cpp b/llvm/lib/IR/Core.cpp
index fb30fbce0ba22e..d6d159ab8b9e83 100644
--- a/llvm/lib/IR/Core.cpp
+++ b/llvm/lib/IR/Core.cpp
@@ -1805,6 +1805,14 @@ LLVMValueRef LLVMBlockAddress(LLVMValueRef F, LLVMBasicBlockRef BB) {
return wrap(BlockAddress::get(unwrap<Function>(F), unwrap(BB)));
}
+LLVMValueRef LLVMGetBlockAddressFunction(LLVMValueRef BlockAddr) {
+ return wrap(unwrap<BlockAddress>(BlockAddr)->getFunction());
+}
+
+LLVMBasicBlockRef LLVMGetBlockAddressBasicBlock(LLVMValueRef BlockAddr) {
+ return wrap(unwrap<BlockAddress>(BlockAddr)->getBasicBlock());
+}
+
/*--.. Operations on global variables, functions, and aliases (globals) ....--*/
LLVMModuleRef LLVMGetGlobalParent(LLVMValueRef Global) {
diff --git a/llvm/unittests/IR/ConstantsTest.cpp b/llvm/unittests/IR/ConstantsTest.cpp
index 314264b77a7101..1d6a92c498b061 100644
--- a/llvm/unittests/IR/ConstantsTest.cpp
+++ b/llvm/unittests/IR/ConstantsTest.cpp
@@ -736,5 +736,44 @@ TEST(ConstantsTest, ComdatUserTracking) {
EXPECT_TRUE(Users.size() == 0);
}
+// Verify that the C API getters for BlockAddress work
+TEST(ConstantsTest, BlockAddressCAPITest) {
+ const char *BlockAddressIR = R"(
+ define void @test_block_address_func() {
+ entry:
+ br label %block_bb_0
+ block_bb_0:
+ ret void
+ }
+ )";
+
+ LLVMContext Context;
+ SMDiagnostic Error;
+ std::unique_ptr<Module> M =
+ parseAssemblyString(BlockAddressIR, Error, Context);
+
+ EXPECT_TRUE(M.get() != nullptr);
+
+ // Get the function
+ auto *Func = M->getFunction("test_block_address_func");
+ EXPECT_TRUE(Func != nullptr);
+
+ // Get the second basic block, since we can't use the entry one
+ const BasicBlock &BB = *(++Func->begin());
+ EXPECT_EQ(BB.getName(), "block_bb_0");
+
+ // Construct the C API values
+ LLVMValueRef BlockAddr = LLVMBlockAddress(wrap(Func), wrap(&BB));
+ EXPECT_TRUE(LLVMIsABlockAddress(BlockAddr));
+
+ // Get the Function/BasicBlock values back out
+ auto *OutFunc = unwrap(LLVMGetBlockAddressFunction(BlockAddr));
+ auto *OutBB = unwrap(LLVMGetBlockAddressBasicBlock(BlockAddr));
+
+ // Verify that they round-tripped properly
+ EXPECT_EQ(Func, OutFunc);
+ EXPECT_EQ(&BB, OutBB);
+}
+
} // end anonymous namespace
} // end namespace llvm