[clang] [CIR] Initial implementation of lowering CIR to MLIR (PR #127835)

[Aaron Ballman via cfe-commits]

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+// RUN: %clang_cc1 -std=c++20 -triple x86_64-unknown-linux-gnu -fclangir -emit-core-mlir %s -o %t.mlir
+// RUN: FileCheck --input-file=%t.mlir %s
+
+char c;
+// CHECK: memref.global "public" @c : memref<i8>
+
+signed char sc;
+// CHECK: memref.global "public" @sc : memref<i8>
+
+unsigned char uc;
+// CHECK: memref.global "public" @uc : memref<i8>
+
+short ss;
+// CHECK: memref.global "public" @ss : memref<i16>
+
+unsigned short us = 100;
+// CHECK: memref.global "public" @us : memref<i16> = dense<100>
+
+int si = 42;
+// CHECK: memref.global "public" @si : memref<i32> = dense<42>
+
+unsigned ui;
+// CHECK: memref.global "public" @ui : memref<i32>
+
+long sl;
+// CHECK: memref.global "public" @sl : memref<i64>
+
+unsigned long ul;
+// CHECK: memref.global "public" @ul : memref<i64>
+
+long long sll;
+// CHECK: memref.global "public" @sll : memref<i64>
+
+unsigned long long ull = 123456;
+// CHECK: memref.global "public" @ull : memref<i64> = dense<123456>
+
+__int128 s128;
+// CHECK: memref.global "public" @s128 : memref<i128>
+
+unsigned __int128 u128;
+// CHECK: memref.global "public" @u128 : memref<i128>
+
+wchar_t wc;
+// CHECK: memref.global "public" @wc : memref<i32>
+
+char8_t c8;
+// CHECK: memref.global "public" @c8 : memref<i8>
+
+char16_t c16;
+// CHECK: memref.global "public" @c16 : memref<i16>
+
+char32_t c32;
+// CHECK: memref.global "public" @c32 : memref<i32>
+
+_BitInt(20) sb20;
+// CHECK: memref.global "public" @sb20 : memref<i20>
+
+unsigned _BitInt(48) ub48;
+// CHECK: memref.global "public" @ub48 : memref<i48>
+
+_Float16 f16;
+// CHECK: memref.global "public" @f16 : memref<f16>
+
+__bf16 bf16;
+// CHECK: memref.global "public" @bf16 : memref<bf16>
+
+float f;
+// CHECK: memref.global "public" @f : memref<f32>
+
+double d = 1.25;
+// CHECK: memref.global "public" @d : memref<f64> = dense<1.250000e+00>
+
+long double ld;
+// CHECK: memref.global "public" @ld : memref<f80>
+
+__float128 f128;
+// CHECK: memref.global "public" @f128 : memref<f128>
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AaronBallman wrote:

What about other builtin types like `__fp16`/`half`, `__ibm128`, `bool`, fixed point types? I suppose another interesting type might be `nullptr_t`?

https://github.com/llvm/llvm-project/pull/127835