[clang] [llvm] Add support for flag output operand "=@cc" for SystemZ. (PR #125970)

[Ulrich Weigand via cfe-commits]

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@@ -0,0 +1,73 @@
+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 6
+// RUN: %clang_cc1 -O2 -triple s390x-linux -emit-llvm -o - %s | FileCheck %s
+
+// CHECK-LABEL: define dso_local signext range(i32 0, 4) i32 @test(
+// CHECK-SAME: i32 noundef signext [[X:%.*]]) local_unnamed_addr #[[ATTR0:[0-9]+]] {
+// CHECK-NEXT:  [[ENTRY:.*:]]
+// CHECK-NEXT:    [[TMP0:%.*]] = tail call { i32, i32 } asm "ahi $0,42\0A", "=d,={@cc},0"(i32 [[X]]) #[[ATTR2:[0-9]+]], !srcloc [[META2:![0-9]+]]
+// CHECK-NEXT:    [[ASMRESULT1:%.*]] = extractvalue { i32, i32 } [[TMP0]], 1
+// CHECK-NEXT:    [[TMP1:%.*]] = icmp ult i32 [[ASMRESULT1]], 4
+// CHECK-NEXT:    tail call void @llvm.assume(i1 [[TMP1]])
+// CHECK-NEXT:    ret i32 [[ASMRESULT1]]
+//
+int test(int x) {
+  int cc;
+  asm ("ahi %[x],42\n" : [x] "+d"(x), "=@cc" (cc));
+  return cc;
+}
+
+// CHECK-LABEL: define dso_local signext range(i32 0, 4) i32 @test_assume_boolean_flag(
+// CHECK-SAME: i32 noundef signext [[X:%.*]]) local_unnamed_addr #[[ATTR0]] {
+// CHECK-NEXT:  [[ENTRY:.*:]]
+// CHECK-NEXT:    [[TMP0:%.*]] = tail call { i32, i32 } asm "ahi $0,42\0A", "=d,={@cc},0"(i32 [[X]]) #[[ATTR2]], !srcloc [[META3:![0-9]+]]
+// CHECK-NEXT:    [[ASMRESULT1:%.*]] = extractvalue { i32, i32 } [[TMP0]], 1
+// CHECK-NEXT:    [[TMP1:%.*]] = icmp ult i32 [[ASMRESULT1]], 4
+// CHECK-NEXT:    tail call void @llvm.assume(i1 [[TMP1]])
+// CHECK-NEXT:    ret i32 [[ASMRESULT1]]
+//
+int test_assume_boolean_flag(int x) {
+  int cc;
+  asm ("ahi %[x],42\n" : [x] "+d"(x), "=@cc" (cc));
+  return cc;
+}
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uweigand wrote:

This test is now exactly identical to the previous one, so I don't think it is needed.

https://github.com/llvm/llvm-project/pull/125970