[clang] [Sparc][clang] make `_Complex` ABI GCC-compatible (PR #212340)

[Folkert de Vries via cfe-commits]

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@@ -0,0 +1,104 @@
+// RUN: %clang_cc1 -triple sparc-unknown-linux-gnu -emit-llvm -o - %s \
+// RUN:   | FileCheck %s --check-prefix=V8
+// RUN: %clang_cc1 -triple sparcv9-unknown-linux-gnu -emit-llvm -o - %s \
+// RUN:   | FileCheck %s --check-prefix=V9
+
+// RUN: %clang_cc1 -triple sparc-unknown-linux-gnu -fclang-abi-compat=23 \
+// RUN:   -emit-llvm -o - %s | FileCheck %s --check-prefix=COMPAT23-V8
+// RUN: %clang_cc1 -triple sparcv9-unknown-linux-gnu -fclang-abi-compat=23 \
+// RUN:   -emit-llvm -o - %s | FileCheck %s --check-prefix=COMPAT23-V9
+
+// Test how SPARC passes and returns `_Complex` values.
+
+// Returns.
+//
+// A `_Complex` value with an integer element type is returned packed into whole
+// integer registers. Clang 23 and before instead gave each part a register of
+// its own on v8, and on v9 left-justified a value narrower than a register the
+// way a small struct is returned. The new behavior matches GCC.
+
+// COMPAT23-V8-LABEL: define{{.*}} { i8, i8 } @ret_complex_char(
+// V8-LABEL:          define{{.*}} i16 @ret_complex_char(
+// COMPAT23-V9-LABEL: define{{.*}} i64 @ret_complex_char(
+// V9-LABEL:          define{{.*}} i16 @ret_complex_char(
+_Complex char ret_complex_char(void) { return 0; }
+
+// COMPAT23-V8-LABEL: define{{.*}} { i16, i16 } @ret_complex_short(
+// V8-LABEL:          define{{.*}} i32 @ret_complex_short(
+// COMPAT23-V9-LABEL: define{{.*}} i64 @ret_complex_short(
+// V9-LABEL:          define{{.*}} i32 @ret_complex_short(
+_Complex short ret_complex_short(void) { return 0; }
+
+// COMPAT23-V8-LABEL: define{{.*}} { i32, i32 } @ret_complex_int(
+// V8-LABEL:          define{{.*}} i64 @ret_complex_int(
+// COMPAT23-V9-LABEL: define{{.*}} i64 @ret_complex_int(
+// V9-LABEL:          define{{.*}} i64 @ret_complex_int(
+_Complex int ret_complex_int(void) { return 0; }
+
+// COMPAT23-V8-LABEL: define{{.*}} { i64, i64 } @ret_complex_long_long(
+// V8-LABEL:          define{{.*}} { i64, i64 } @ret_complex_long_long(
+// COMPAT23-V9-LABEL: define{{.*}} { i64, i64 } @ret_complex_long_long(
+// V9-LABEL:          define{{.*}} { i64, i64 } @ret_complex_long_long(
+_Complex long long ret_complex_long_long(void) { return 0; }
+
+// COMPAT23-V8-LABEL: define{{.*}} { float, float } @ret_complex_float(
+// V8-LABEL:          define{{.*}} { float, float } @ret_complex_float(
+// COMPAT23-V9-LABEL: define{{.*}} inreg { float, float } @ret_complex_float(
+// V9-LABEL:          define{{.*}} inreg { float, float } @ret_complex_float(
+_Complex float ret_complex_float(void) { return 0; }
+
+// COMPAT23-V8-LABEL: define{{.*}} { double, double } @ret_complex_double(
+// V8-LABEL:          define{{.*}} { double, double } @ret_complex_double(
+// COMPAT23-V9-LABEL: define{{.*}} { double, double } @ret_complex_double(
+// V9-LABEL:          define{{.*}} { double, double } @ret_complex_double(
+_Complex double ret_complex_double(void) { return 0; }
+
+// COMPAT23-V8-LABEL: define{{.*}} inreg { fp128, fp128 } @ret_complex_long_double(
+// V8-LABEL:          define{{.*}} inreg { fp128, fp128 } @ret_complex_long_double(
+// COMPAT23-V9-LABEL: define{{.*}} { fp128, fp128 } @ret_complex_long_double(
+// V9-LABEL:          define{{.*}} { fp128, fp128 } @ret_complex_long_double(
+_Complex long double ret_complex_long_double(void) { return 0; }
+
+// Arguments.
+
+// COMPAT23-V8-LABEL: define{{.*}} void @arg_complex_char(ptr noundef byval({ i8, i8 }) align 1 %c)
+// V8-LABEL:          define{{.*}} void @arg_complex_char(i16 noundef %c.coerce)
+// COMPAT23-V9-LABEL: define{{.*}} void @arg_complex_char(i64 %c.coerce)
+// V9-LABEL:          define{{.*}} void @arg_complex_char(i16 noundef %c.coerce)
+void arg_complex_char(_Complex char c) {}
+
+// COMPAT23-V8-LABEL: define{{.*}} void @arg_complex_short(ptr noundef byval({ i16, i16 }) align 2 %c)
+// V8-LABEL:          define{{.*}} void @arg_complex_short(i32 noundef %c.coerce)
+// COMPAT23-V9-LABEL: define{{.*}} void @arg_complex_short(i64 %c.coerce)
+// V9-LABEL:          define{{.*}} void @arg_complex_short(i32 noundef %c.coerce)
+void arg_complex_short(_Complex short c) {}
+
+// COMPAT23-V8-LABEL: define{{.*}} void @arg_complex_int(ptr noundef byval({ i32, i32 }) align 4 %c)
+// V8-LABEL:          define{{.*}} void @arg_complex_int(i64 noundef %c.coerce)
+// COMPAT23-V9-LABEL: define{{.*}} void @arg_complex_int(i64 noundef %c.coerce)
+// V9-LABEL:          define{{.*}} void @arg_complex_int(i64 noundef %c.coerce)
+void arg_complex_int(_Complex int c) {}
+
+// COMPAT23-V8-LABEL: define{{.*}} void @arg_complex_long_long(ptr noundef byval({ i64, i64 }) align 8 %c)
+// V8-LABEL:          define{{.*}} void @arg_complex_long_long(ptr noundef byval({ i64, i64 }) align 8 %c)
+// COMPAT23-V9-LABEL: define{{.*}} void @arg_complex_long_long(i64 noundef %c.coerce0, i64 noundef %c.coerce1)
+// V9-LABEL:          define{{.*}} void @arg_complex_long_long(i64 noundef %c.coerce0, i64 noundef %c.coerce1)
+void arg_complex_long_long(_Complex long long c) {}
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folkertdev wrote:

Well this creates kind of a mess but if you prefer it, sure.

https://github.com/llvm/llvm-project/pull/212340