[llvm] [AArch64] improve zero-cycle regmov test (PR #143680)

[Tomer Shafir via llvm-commits]

https://github.com/tomershafir updated https://github.com/llvm/llvm-project/pull/143680

>From 13052e511aca243a14f9660ab6fc8e1e862a34e6 Mon Sep 17 00:00:00 2001
From: tomershafir <tomer.shafir8 at gmail.com>
Date: Wed, 11 Jun 2025 13:33:03 +0300
Subject: [PATCH] [AArch64] improve zero-cycle regmov test

- Add a `gpr32` suffix to test name to denote the specific register class being checked
- Expand `-mtriple=arm64-apple-ios` to `-march=arm64` to broaden the test context to the generic architecture, as the specific triple is not required
- Port `bl` match to Linux too via the regex: `{{_?foo}}`
- Advance `-mcpu=cyclone` to the newer M series major `-mcpu=apple-m1`
- Use `-mcpu` so that `-mattr=-zcm` has a real effect
- Add a test that generic arm64 doesn't optimize for ZCM
- Distinguish 4 different assembly layouts: NOTCPU, CPU, NOTATTR, ATTR
- Fix broken test logic, for example: `; NOT: mov [[REG2:w[0-9]+]], w3` matched `mov w1, w3` then `REG2` captured `w1` but then `; NOT: mov w1, [[REG2]]` matched by prefix `mov, w1, w19` even though it should have matched `mov w1, w1`. This change adds explicit matches for all of the generated copies, and `--match-full-lines` param to FileCheck.
- Remove nownwind and ssp from t function decleration
- Remove nounwind from foo call sites
- Separate different outputs for readability
- Change return type from `i32` to `void`
---
 .../AArch64/arm64-zero-cycle-regmov-gpr32.ll  | 45 +++++++++++++++++++
 .../AArch64/arm64-zero-cycle-regmov.ll        | 23 ----------
 2 files changed, 45 insertions(+), 23 deletions(-)
 create mode 100644 llvm/test/CodeGen/AArch64/arm64-zero-cycle-regmov-gpr32.ll
 delete mode 100644 llvm/test/CodeGen/AArch64/arm64-zero-cycle-regmov.ll

diff --git a/llvm/test/CodeGen/AArch64/arm64-zero-cycle-regmov-gpr32.ll b/llvm/test/CodeGen/AArch64/arm64-zero-cycle-regmov-gpr32.ll
new file mode 100644
index 0000000000000..4d15ee89177cc
--- /dev/null
+++ b/llvm/test/CodeGen/AArch64/arm64-zero-cycle-regmov-gpr32.ll
@@ -0,0 +1,45 @@
+; RUN: llc < %s -march=arm64 | FileCheck %s -check-prefixes=NOTCPU --match-full-lines
+; RUN: llc < %s -mtriple=arm64-apple-macosx -mcpu=apple-m1 | FileCheck %s -check-prefixes=CPU --match-full-lines
+; RUN: llc < %s -mtriple=arm64-apple-macosx -mcpu=apple-m1 -mattr=-zcm | FileCheck %s -check-prefixes=NOTATTR --match-full-lines
+; RUN: llc < %s -mtriple=arm64-apple-macosx -mattr=+zcm | FileCheck %s -check-prefixes=ATTR --match-full-lines
+
+define void @t(i32 %a, i32 %b, i32 %c, i32 %d) {
+entry:
+; CHECK-LABEL: t:
+; NOTCPU: mov w0, w2
+; NOTCPU: mov w1, w3
+; NOTCPU: mov [[REG2:w[0-9]+]], w3
+; NOTCPU: mov [[REG1:w[0-9]+]], w2
+; NOTCPU: bl {{_?foo}}
+; NOTCPU: mov w0, [[REG1]]
+; NOTCPU: mov w1, [[REG2]]
+
+; CPU: mov [[REG2:x[0-9]+]], x3
+; CPU: mov [[REG1:x[0-9]+]], x2
+; CPU: mov x0, x2
+; CPU: mov x1, x3
+; CPU: bl {{_?foo}}
+; CPU: mov x0, [[REG1]]
+; CPU: mov x1, [[REG2]]
+
+; NOTATTR: mov [[REG2:w[0-9]+]], w3
+; NOTATTR: mov [[REG1:w[0-9]+]], w2
+; NOTATTR: mov w0, w2
+; NOTATTR: mov w1, w3
+; NOTATTR: bl {{_?foo}}
+; NOTATTR: mov w0, [[REG1]]
+; NOTATTR: mov w1, [[REG2]]
+
+; ATTR: mov x0, x2
+; ATTR: mov x1, x3
+; ATTR: mov [[REG2:x[0-9]+]], x3
+; ATTR: mov [[REG1:x[0-9]+]], x2
+; ATTR: bl {{_?foo}}
+; ATTR: mov x0, [[REG1]]
+; ATTR: mov x1, [[REG2]]
+  %call = call i32 @foo(i32 %c, i32 %d)
+  %call1 = call i32 @foo(i32 %c, i32 %d)
+  unreachable
+}
+
+declare i32 @foo(i32, i32)
diff --git a/llvm/test/CodeGen/AArch64/arm64-zero-cycle-regmov.ll b/llvm/test/CodeGen/AArch64/arm64-zero-cycle-regmov.ll
deleted file mode 100644
index b390853d44bff..0000000000000
--- a/llvm/test/CodeGen/AArch64/arm64-zero-cycle-regmov.ll
+++ /dev/null
@@ -1,23 +0,0 @@
-; RUN: llc < %s -mtriple=arm64-apple-ios -mattr=-zcm   | FileCheck %s -check-prefixes=CHECK,NOT
-; RUN: llc < %s -mtriple=arm64-apple-ios -mattr=+zcm   | FileCheck %s -check-prefixes=CHECK,YES
-; RUN: llc < %s -mtriple=arm64-apple-ios -mcpu=cyclone | FileCheck %s -check-prefixes=CHECK,YES
-
-; rdar://12254953
-define i32 @t(i32 %a, i32 %b, i32 %c, i32 %d) nounwind ssp {
-entry:
-; CHECK-LABEL: t:
-; NOT: mov [[REG2:w[0-9]+]], w3
-; NOT: mov [[REG1:w[0-9]+]], w2
-; YES: mov [[REG2:x[0-9]+]], x3
-; YES: mov [[REG1:x[0-9]+]], x2
-; CHECK: bl _foo
-; NOT: mov w0, [[REG1]]
-; NOT: mov w1, [[REG2]]
-; YES: mov x0, [[REG1]]
-; YES: mov x1, [[REG2]]
-  %call = call i32 @foo(i32 %c, i32 %d) nounwind
-  %call1 = call i32 @foo(i32 %c, i32 %d) nounwind
-  unreachable
-}
-
-declare i32 @foo(i32, i32)