[CLANG] Fixes the issue with using bool in builtin_bswapg

[ebinjose02]

Fixes #168690
Prevents assertion in CGBuiltin for i1 - returns identity. Created test file for the same.

[github-actions]

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[llvmbot]

@llvm/pr-subscribers-clang

Author: Ebin Jose (ebinjose02)

Changes

Fixes #168690
Prevents assertion in CGBuiltin for i1 - returns identity. Created test file for the same.

---

Full diff: https://github.com/llvm/llvm-project/pull/169285.diff

2 Files Affected:

• (modified) clang/lib/CodeGen/CGBuiltin.cpp (+2)
• (added) clang/test/CodeGen/builtin_bswapg.cpp (+8)

diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 93f691e4c2267..8bcc2c8e7d8fe 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -3653,6 +3653,8 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
     Value *ArgValue = EmitScalarExpr(E->getArg(0));
     llvm::IntegerType *IntTy = cast<llvm::IntegerType>(ArgValue->getType());
     assert(IntTy && "LLVM's __builtin_bswapg only supports integer variants");
+    if (IntTy->getBitWidth() == 1)
+      return RValue::get(ArgValue);
     assert(((IntTy->getBitWidth() % 16 == 0 && IntTy->getBitWidth() != 0) ||
             IntTy->getBitWidth() == 8) &&
            "LLVM's __builtin_bswapg only supports integer variants that has a "
diff --git a/clang/test/CodeGen/builtin_bswapg.cpp b/clang/test/CodeGen/builtin_bswapg.cpp
new file mode 100644
index 0000000000000..8e9af98a58d35
--- /dev/null
+++ b/clang/test/CodeGen/builtin_bswapg.cpp
@@ -0,0 +1,8 @@
+// RUN: %clang_cc1 -triple x86_64 -O0 -emit-llvm -o - %s | FileCheck %s
+
+auto test_bswapg(bool c) {
+  return __builtin_bswapg(c);
+}
+
+// CHECK-LABEL: define{{.*}} i1 @_Z11test_bswapgb(
+// CHECK: ret i1 %{{.*}}

[llvmbot]

@llvm/pr-subscribers-clang-codegen

Author: Ebin Jose (ebinjose02)

Changes

Fixes #168690
Prevents assertion in CGBuiltin for i1 - returns identity. Created test file for the same.

---

Full diff: https://github.com/llvm/llvm-project/pull/169285.diff

2 Files Affected:

• (modified) clang/lib/CodeGen/CGBuiltin.cpp (+2)
• (added) clang/test/CodeGen/builtin_bswapg.cpp (+8)

diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 93f691e4c2267..8bcc2c8e7d8fe 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -3653,6 +3653,8 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
     Value *ArgValue = EmitScalarExpr(E->getArg(0));
     llvm::IntegerType *IntTy = cast<llvm::IntegerType>(ArgValue->getType());
     assert(IntTy && "LLVM's __builtin_bswapg only supports integer variants");
+    if (IntTy->getBitWidth() == 1)
+      return RValue::get(ArgValue);
     assert(((IntTy->getBitWidth() % 16 == 0 && IntTy->getBitWidth() != 0) ||
             IntTy->getBitWidth() == 8) &&
            "LLVM's __builtin_bswapg only supports integer variants that has a "
diff --git a/clang/test/CodeGen/builtin_bswapg.cpp b/clang/test/CodeGen/builtin_bswapg.cpp
new file mode 100644
index 0000000000000..8e9af98a58d35
--- /dev/null
+++ b/clang/test/CodeGen/builtin_bswapg.cpp
@@ -0,0 +1,8 @@
+// RUN: %clang_cc1 -triple x86_64 -O0 -emit-llvm -o - %s | FileCheck %s
+
+auto test_bswapg(bool c) {
+  return __builtin_bswapg(c);
+}
+
+// CHECK-LABEL: define{{.*}} i1 @_Z11test_bswapgb(
+// CHECK: ret i1 %{{.*}}

[github-actions]

🐧 Linux x64 Test Results

• 84739 tests passed
• 1104 tests skipped
• 1 test failed

Failed Tests

(click on a test name to see its output)

Clang

Clang.CodeGen/builtin_bswapg.c

Exit Code: 2

Command Output (stdout):
--
# RUN: at line 1
/home/gha/actions-runner/_work/llvm-project/llvm-project/build/bin/clang -cc1 -internal-isystem /home/gha/actions-runner/_work/llvm-project/llvm-project/build/lib/clang/22/include -nostdsysteminc -triple x86_64 -O0 -emit-llvm -o - /home/gha/actions-runner/_work/llvm-project/llvm-project/clang/test/CodeGen/builtin_bswapg.c | /home/gha/actions-runner/_work/llvm-project/llvm-project/build/bin/FileCheck /home/gha/actions-runner/_work/llvm-project/llvm-project/clang/test/CodeGen/builtin_bswapg.c
# executed command: /home/gha/actions-runner/_work/llvm-project/llvm-project/build/bin/clang -cc1 -internal-isystem /home/gha/actions-runner/_work/llvm-project/llvm-project/build/lib/clang/22/include -nostdsysteminc -triple x86_64 -O0 -emit-llvm -o - /home/gha/actions-runner/_work/llvm-project/llvm-project/clang/test/CodeGen/builtin_bswapg.c
# .---command stderr------------
# | /home/gha/actions-runner/_work/llvm-project/llvm-project/clang/test/CodeGen/builtin_bswapg.c:3:18: error: unknown type name 'bool'
# |     3 | auto test_bswapg(bool c) {
# |       |                  ^
# | /home/gha/actions-runner/_work/llvm-project/llvm-project/clang/test/CodeGen/builtin_bswapg.c:3:6: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]
# |     3 | auto test_bswapg(bool c) {
# |       | ~~~~ ^
# |       | int
# | /home/gha/actions-runner/_work/llvm-project/llvm-project/clang/test/CodeGen/builtin_bswapg.c:3:1: error: illegal storage class on function
# |     3 | auto test_bswapg(bool c) {
# |       | ^
# | 3 errors generated.
# `-----------------------------
# error: command failed with exit status: 1
# executed command: /home/gha/actions-runner/_work/llvm-project/llvm-project/build/bin/FileCheck /home/gha/actions-runner/_work/llvm-project/llvm-project/clang/test/CodeGen/builtin_bswapg.c
# .---command stderr------------
# | FileCheck error: '<stdin>' is empty.
# | FileCheck command line:  /home/gha/actions-runner/_work/llvm-project/llvm-project/build/bin/FileCheck /home/gha/actions-runner/_work/llvm-project/llvm-project/clang/test/CodeGen/builtin_bswapg.c
# `-----------------------------
# error: command failed with exit status: 2

--

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