https://github.com/xakep8 updated 
https://github.com/llvm/llvm-project/pull/214931

>From 92b788bc02d91996ff986b3f3f54927bcf90ca64 Mon Sep 17 00:00:00 2001
From: Kunal Dubey <[email protected]>
Date: Sat, 8 Aug 2026 10:19:23 +0530
Subject: [PATCH 1/3] [CIR] Lowering __builtin_stdc_trailing_zeros

Added CIRGen support for __builtin_stdc_trailing_zeros by lowering it to
cir.ctz with zero behaviour defined, matching with the C23 stdbit
semantics.

Added CodeGen test for the same.
---
 clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp           |  7 +++++++
 clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c | 10 ++++++++++
 2 files changed, 17 insertions(+)
 create mode 100644 clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c

diff --git a/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp 
b/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
index 1efe2b81d5cae..2eb9d6c3bb661 100644
--- a/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
@@ -1247,6 +1247,13 @@ RValue CIRGenFunction::emitBuiltinExpr(const GlobalDecl 
&gd, unsigned builtinID,
                                            getTarget().isCLZForZeroUndef());
   case Builtin::BI__builtin_ctzg:
     return emitBuiltinBitOpWithFallback<cir::BitCtzOp>(*this, e);
+  case Builtin::BIstdc_trailing_zeros_uc:
+  case Builtin::BIstdc_trailing_zeros_us:
+  case Builtin::BIstdc_trailiing_zeros_ui:
+  case Builtin::BIstdc_trailing_zeros_ul:
+  case Builtin::BIstdc_trailing_zeros_ull:
+  case Builtin::BI__builtin_stdc_trailing_zeros:
+    return emitBuiltinBitOp<cir::BitCtzOp>(*this, e, /*poisonZero=*/false);
 
   case Builtin::BI__builtin_clzs:
   case Builtin::BI__builtin_clz:
diff --git a/clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c 
b/clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c
new file mode 100644
index 0000000000000..6d285c259a96f
--- /dev/null
+++ b/clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c
@@ -0,0 +1,10 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fclangir -emit-cir %s -o 
- | FileCheck %s
+
+void test_stdc_trailing_zeros(unsigned long long x) {
+  int cnt = __builtin_stdc_trailing_zeros(x);
+  (void)cnt;
+}
+
+// CHECK-LABEL: test_stdc_trailing_zeros
+// CHECK: cir.ctz
+// CHECK-NOT: poison_zero

>From 06447c7643d7cb9a65d533d440b98411b6d02299 Mon Sep 17 00:00:00 2001
From: Kunal Dubey <[email protected]>
Date: Sat, 8 Aug 2026 11:31:41 +0530
Subject: [PATCH 2/3] [CIR] Lowering __builtin_stdc_leading_zeros

Added CIRGen support for __builtin_stdc_leading_zeros by lowering to
cir.clz with zero behaviour defined, matching C23 stdbit semantics.

Added CodeGen test for the same.
---
 clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp       |  8 ++++++++
 .../CIR/CodeGenBuiltins/builtin-stdc-bit.c    | 19 +++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp 
b/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
index 2eb9d6c3bb661..bbc82f33571d4 100644
--- a/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
@@ -1255,6 +1255,14 @@ RValue CIRGenFunction::emitBuiltinExpr(const GlobalDecl 
&gd, unsigned builtinID,
   case Builtin::BI__builtin_stdc_trailing_zeros:
     return emitBuiltinBitOp<cir::BitCtzOp>(*this, e, /*poisonZero=*/false);
 
+  case Builtin::BIstdc_leading_zeros_uc:
+  case Builtin::BIstdc_leading_zeros_us:
+  case Builtin::BIstdc_leading_zeros_ui:
+  case Builtin::BIstdc_leading_zeros_ul:
+  case Builtin::BIstdc_leading_zeros_ull:
+  case Builtin::BI__builtin_stdc_leading_zeros:
+    return emitBuiltinBitOp<cir::BitClzOp>(*this, e, /*poisonZero=*/false);
+
   case Builtin::BI__builtin_clzs:
   case Builtin::BI__builtin_clz:
   case Builtin::BI__builtin_clzl:
diff --git a/clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c 
b/clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c
index 6d285c259a96f..1f127821673d2 100644
--- a/clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c
+++ b/clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c
@@ -8,3 +8,22 @@ void test_stdc_trailing_zeros(unsigned long long x) {
 // CHECK-LABEL: test_stdc_trailing_zeros
 // CHECK: cir.ctz
 // CHECK-NOT: poison_zero
+// CHECK: cir.return
+
+void test_stdc_leading_zeros(unsigned x) {
+  return __builtin_stdc_trailing_zeros(x);
+}
+
+// CHECK-LABEL: test_stdc_leading_zeros
+// CHECK: cir.clz
+// CHECK-NOT: poison_zero
+// CHECK: cir.return
+
+void test_stdc_leading_zeros_ui(unsigned x) {
+  return stdc_leading_zeros_ui(x);
+}
+
+// CHECK-LABEL: test_stdc_leading_zeros_ui
+// CHECK: cir.clz
+// CHECK-NOT: poison_zero
+// CHECK: cir.return

>From 7a91d44a11c0774d2c8f149eb66ee3593add00eb Mon Sep 17 00:00:00 2001
From: Kunal Dubey <[email protected]>
Date: Sun, 9 Aug 2026 16:33:16 +0530
Subject: [PATCH 3/3] [CIR] Lowering __builtin_stdc_count_ones

Added CIRGen support for lowering of __builtin_stdc_count_ones by
lowering to cir.popcount, matching with the C23 stdbit semantics.

Added test for the same.
---
 clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp       | 10 ++++++++-
 .../CIR/CodeGenBuiltins/builtin-stdc-bit.c    | 22 ++++++++++++++++---
 2 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp 
b/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
index bbc82f33571d4..d27ace31cef78 100644
--- a/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
@@ -1249,7 +1249,7 @@ RValue CIRGenFunction::emitBuiltinExpr(const GlobalDecl 
&gd, unsigned builtinID,
     return emitBuiltinBitOpWithFallback<cir::BitCtzOp>(*this, e);
   case Builtin::BIstdc_trailing_zeros_uc:
   case Builtin::BIstdc_trailing_zeros_us:
-  case Builtin::BIstdc_trailiing_zeros_ui:
+  case Builtin::BIstdc_trailing_zeros_ui:
   case Builtin::BIstdc_trailing_zeros_ul:
   case Builtin::BIstdc_trailing_zeros_ull:
   case Builtin::BI__builtin_stdc_trailing_zeros:
@@ -1263,6 +1263,14 @@ RValue CIRGenFunction::emitBuiltinExpr(const GlobalDecl 
&gd, unsigned builtinID,
   case Builtin::BI__builtin_stdc_leading_zeros:
     return emitBuiltinBitOp<cir::BitClzOp>(*this, e, /*poisonZero=*/false);
 
+  case Builtin::BIstdc_count_ones_uc:
+  case Builtin::BIstdc_count_ones_us:
+  case Builtin::BIstdc_count_ones_ui:
+  case Builtin::BIstdc_count_ones_ul:
+  case Builtin::BIstdc_count_ones_ull:
+  case Builtin::BI__builtin_stdc_count_ones:
+    return emitBuiltinBitOp<cir::BitPopcountOp>(*this, e);
+
   case Builtin::BI__builtin_clzs:
   case Builtin::BI__builtin_clz:
   case Builtin::BI__builtin_clzl:
diff --git a/clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c 
b/clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c
index 1f127821673d2..e9d5b25a10f0e 100644
--- a/clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c
+++ b/clang/test/CIR/CodeGenBuiltins/builtin-stdc-bit.c
@@ -10,8 +10,8 @@ void test_stdc_trailing_zeros(unsigned long long x) {
 // CHECK-NOT: poison_zero
 // CHECK: cir.return
 
-void test_stdc_leading_zeros(unsigned x) {
-  return __builtin_stdc_trailing_zeros(x);
+unsigned test_stdc_leading_zeros(unsigned x) {
+  return __builtin_stdc_leading_zeros(x);
 }
 
 // CHECK-LABEL: test_stdc_leading_zeros
@@ -19,7 +19,7 @@ void test_stdc_leading_zeros(unsigned x) {
 // CHECK-NOT: poison_zero
 // CHECK: cir.return
 
-void test_stdc_leading_zeros_ui(unsigned x) {
+unsigned test_stdc_leading_zeros_ui(unsigned x) {
   return stdc_leading_zeros_ui(x);
 }
 
@@ -27,3 +27,19 @@ void test_stdc_leading_zeros_ui(unsigned x) {
 // CHECK: cir.clz
 // CHECK-NOT: poison_zero
 // CHECK: cir.return
+
+unsigned test_stdc_count_ones(unsigned x) {
+  return __builtin_stdc_count_ones(x);
+}
+
+// CHECK-LABEL: test_stdc_count_ones
+// CHECK: cir.popcount
+// CHECK: cir.return
+
+unsigned test_stdc_count_ones_ui(unsigned x) {
+  return stdc_count_ones_ui(x);
+}
+
+// CHECK-LABEL: test_stdc_count_ones_ui
+// CHECK: cir.popcount
+// CHECK: cir.return

_______________________________________________
cfe-commits mailing list
[email protected]
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits

Reply via email to