[clang] [CIR] Add support for discrete bit-field (PR #156085)

[Bruno Cardoso Lopes via cfe-commits]

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@@ -0,0 +1,75 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -mms-bitfields -fclangir -emit-cir %s -o %t.cir
+// RUN: FileCheck --input-file=%t.cir %s --check-prefix=CIR
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -mms-bitfields -fclangir -emit-llvm %s -o %t-cir.ll
+// RUN: FileCheck --input-file=%t-cir.ll %s --check-prefix=LLVM
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -mms-bitfields -emit-llvm %s -o %t.ll
+// RUN: FileCheck --input-file=%t.ll %s --check-prefix=OGCG
+
+struct s1 {
+  int       f32 : 2;
+  long long f64 : 30;
+} s1;
+
+// CIR-DAG: !rec_s1 = !cir.record<struct "s1" {!s32i, !s64i}>
+// LLVM-DAG: %struct.s1 = type { i32, i64 }
+// OGCG-DAG: %struct.s1 = type { i32, i64 }
+
+struct s2 {
+    int  a : 24;
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bcardosolopes wrote:

two spaces, need to fix more below as well

https://github.com/llvm/llvm-project/pull/156085