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File 0567-AArch64-Correct-test-of-int-typed-return-value.patch of Package erlang (Revision 54461a2357af3de1f765489d2fd0ee14)

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From 63d1bee55eb3e81ca3081d145a228ff0a5995ffc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= <bjorn@erlang.org>
Date: Mon, 27 Nov 2023 12:26:23 +0100
Subject: [PATCH] AArch64: Correct test of int-typed return value

The function `eq()` returns an `int`, but the code generated by the
JIT for AArch64 tested the entire `x0` (ARG1) register. That happened
to work because the way `eq()` is implemented, it does not return
random garbage in the upper part of `x0`. Change the test to only
check the lower part of ARG1 in case the implementation of `eq()`
changes in the future.
---
 erts/emulator/beam/jit/arm/instr_common.cpp     | 4 ++--
 erts/emulator/beam/jit/arm/instr_guard_bifs.cpp | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/erts/emulator/beam/jit/arm/instr_common.cpp b/erts/emulator/beam/jit/arm/instr_common.cpp
index 06ebae04b9..d244d8df1e 100644
--- a/erts/emulator/beam/jit/arm/instr_common.cpp
+++ b/erts/emulator/beam/jit/arm/instr_common.cpp
@@ -1500,7 +1500,7 @@ void BeamModuleAssembler::emit_is_eq_exact(const ArgLabel &Fail,
 
     emit_leave_runtime();
 
-    a.cbz(ARG1, resolve_beam_label(Fail, disp1MB));
+    a.cbz(ARG1.w(), resolve_beam_label(Fail, disp1MB));
 
     a.bind(next);
 }
@@ -1578,7 +1578,7 @@ void BeamModuleAssembler::emit_is_ne_exact(const ArgLabel &Fail,
 
     emit_leave_runtime();
 
-    a.cbnz(ARG1, resolve_beam_label(Fail, disp1MB));
+    a.cbnz(ARG1.w(), resolve_beam_label(Fail, disp1MB));
 
     a.bind(next);
 }
diff --git a/erts/emulator/beam/jit/arm/instr_guard_bifs.cpp b/erts/emulator/beam/jit/arm/instr_guard_bifs.cpp
index c24ca4831f..2386a4a1bb 100644
--- a/erts/emulator/beam/jit/arm/instr_guard_bifs.cpp
+++ b/erts/emulator/beam/jit/arm/instr_guard_bifs.cpp
@@ -81,7 +81,7 @@ void BeamGlobalAssembler::emit_bif_is_eq_exact_shared() {
     emit_leave_runtime();
     emit_leave_runtime_frame();
 
-    a.cbz(ARG1, fail);
+    a.cbz(ARG1.w(), fail);
 
     a.bind(succ);
     {
@@ -113,7 +113,7 @@ void BeamGlobalAssembler::emit_bif_is_ne_exact_shared() {
     emit_leave_runtime();
     emit_leave_runtime_frame();
 
-    a.cbnz(ARG1, fail);
+    a.cbnz(ARG1.w(), fail);
 
     a.bind(succ);
     {
-- 
2.35.3

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File 0567-AArch64-Correct-test-of-int-typed-return-value.patch of Package erlang (Revision 54461a2357af3de1f765489d2fd0ee14)

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