Add muldiv/rd_tsc support for arm64 platform.

Signed-off-by: Haibo Xu <haibo.xu@arm.com>
Change-Id: If35459be78e023346a140184401172f8e023c7f9
PiperOrigin-RevId: 231638020

1 files changed, 44 insertions, 0 deletions

diff --git a/pkg/sentry/time/muldiv_arm64.s b/pkg/sentry/time/muldiv_arm64.s
new file mode 100644
index 000000000..5fa82a136
--- /dev/null
+++ b/pkg/sentry/time/muldiv_arm64.s
@@ -0,0 +1,44 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "textflag.h"
+
+// Documentation is available in parameters.go.
+//
+// func muldiv64(value, multiplier, divisor uint64) (uint64, bool)
+TEXT ·muldiv64(SB),NOSPLIT,$40-33
+    MOVD    value+0(FP), R0
+    MOVD    multiplier+8(FP), R1
+    MOVD    divisor+16(FP), R2
+
+    UMULH   R0, R1, R3
+    MUL     R0, R1, R4
+
+    CMP     R2, R3
+    BHS     overflow
+
+    MOVD    R3, 8(RSP)
+    MOVD    R4, 16(RSP)
+    MOVD    R2, 24(RSP)
+    CALL    ·divWW(SB)
+    MOVD    32(RSP), R0
+    MOVD    R0, result+24(FP)
+    MOVD    $1, R0
+    MOVB    R0, ok+32(FP)
+    RET
+
+overflow:
+    MOVD    ZR, result+24(FP)
+    MOVB    ZR, ok+32(FP)
+    RET