PPC/s390: [arm][arm64] Fix --trace-osr

Port 1fcfc6a6

Original Commit Message:

    Read only a single byte of FLAG_trace_osr in assembly builtin code to
    make asan happy in the simulator.

R=cbruni@chromium.org, joransiu@ca.ibm.com, junyan@redhat.com, midawson@redhat.com
BUG=
LOG=N

Change-Id: I29d21bfb79999e5e73ca546368bdf812a2353eef
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3648167Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Milad Farazmand <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/main@{#80552}

src/builtins/ppc/builtins-ppc.cc

@@ -430,7 +430,7 @@ void OnStackReplacement(MacroAssembler* masm, OsrSourceTier source,
   {
     Label next;
     __ Move(r4, ExternalReference::address_of_FLAG_trace_osr());
-    __ LoadU64(r4, MemOperand(r4));
+    __ LoadU8(r4, MemOperand(r4));
     __ andi(r0, r4, Operand(0xFF));  // Mask to the LSB.
     __ beq(&next, cr0);
 

src/builtins/s390/builtins-s390.cc

@@ -293,7 +293,7 @@ void OnStackReplacement(MacroAssembler* masm, OsrSourceTier source,
   {
     Label next;
     __ Move(r3, ExternalReference::address_of_FLAG_trace_osr());
-    __ LoadU64(r3, MemOperand(r3));
+    __ LoadU8(r3, MemOperand(r3));
     __ tmll(r3, Operand(0xFF));  // Mask to the LSB.
     __ beq(&next);