[Flang2] Fix duplicate TBAA type systems across modules

In Flang, functions within the same module are assigned unique TBAA
type system IDs based on their order, but functions in different
modules can unintentionally receive the same ID, leading to incorrect
non-aliasing results. This commit resolves the issue by appending a
hash of the module name to each function type system metadata, ensuring
unique type systems across modules and preventing aliasing errors.

test/llvm_ir_correct/tbaa_multimod_01.f90

@@ -0,0 +1,21 @@
+! This test contians two files, tbaa_multimod_01.f90 and tbaa_multimod_01_input.f90
+! RUN: %flang -emit-llvm -c -O3 %s -o %t.bc
+! RUN: %flang -emit-llvm -c -O3 %S/tbaa_multimod_01_input.f90 -o %t2.bc
+! RUN: llvm-link -o %t3.bc %t.bc %t2.bc
+! RUN: opt -aa-trace -O3 -o - %t3.bc 2>&1 | FileCheck %s 
+! CHECK-NOT: End ptr getelementptr (%struct.BSS1, ptr @.BSS1, i64 -1, i32 0, i64 16) @ LocationSize::precise(16), ptr inttoptr (i64 56 to ptr) @ LocationSize::precise(8) = NoAlias
+
+program main
+  implicit none
+  integer, parameter :: n = 5
+  real :: arr(n)
+  integer :: i
+  i = 0
+  arr = 3.2
+  arr(i) = 4
+  call modify1(arr)
+  call modify2(arr)
+
+  arr(i) = arr(i) + 2.5
+  call printout(arr)
+end program main

test/llvm_ir_correct/tbaa_multimod_01_input.f90

@@ -0,0 +1,25 @@
+! A part of the test provided in tbaa_multimod_01.f90
+! Empty RUN and CHECK to prevent error
+! RUN: echo "NoCheck" | FileCheck %s
+! CHECK: NoCheck
+
+subroutine modify1(arr)
+  implicit none
+  real, intent(inout) :: arr(:)
+  arr(0) = arr(0) + 0.5
+end subroutine modify1
+
+subroutine modify2(arr)
+  implicit none
+  real, intent(inout) :: arr(:)
+  arr(2) = arr(2) + 1.5
+end subroutine modify2
+
+subroutine printout(arr)
+  implicit none
+  real, intent(in) :: arr(:)
+  integer :: i
+  do i = 1, size(arr)
+    print arr(i), " "
+  enddo
+end subroutine printout

test/llvm_ir_correct/tbaa_multimod_02.f90

@@ -0,0 +1,17 @@
+! This test contians two files, tbaa_multimod_02.f90 and tbaa_multimod_02_input.f90
+! RUN: %flang -emit-llvm -c -O3 %s -o %t.bc
+! RUN: %flang -emit-llvm -c -O3 %S/tbaa_multimod_02_input.f90 -o %t2.bc
+! RUN: llvm-link -o %t3.bc %t.bc %t2.bc
+! RUN: opt -aa-trace -O3 -o - %t3.bc 2>&1 | FileCheck %s 
+! CHECK-NOT: End ptr getelementptr inbounds (%struct.BSS1, ptr @.BSS1, i64 0, i32 0, i64 16) @ LocationSize::precise(4), ptr inttoptr (i64 56 to ptr) @ LocationSize::precise(8) = NoAlias
+
+program main
+  implicit none
+  integer, parameter :: n = 5
+  real :: arr(n)
+  integer :: i
+  arr = 1
+  call to_load(arr)
+  arr(0) = 4
+  call to_load(arr)
+end program main

test/llvm_ir_correct/tbaa_multimod_02_input.f90

@@ -0,0 +1,13 @@
+! A part of the test provided in tbaa_multimod_02.f90
+! Empty RUN and CHECK to prevent error
+! RUN: echo "NoCheck" | FileCheck %s
+! CHECK: NoCheck
+
+subroutine to_load(arr)
+  implicit none
+  real, intent(inout) :: arr(:)
+  real :: var
+  var = arr(0)
+  var = var * 2
+  print var
+end subroutine to_load

tools/flang2/flang2exe/cgmain.cpp

@@ -10,29 +10,30 @@
    \brief Main source module to translate into LLVM
  */
 
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <string>
 #include "cgmain.h"
+#include "cg.h"
+#include "dinit.h"
 #include "dtypeutl.h"
-#include "ll_ftn.h"
-#include "exp_rte.h"
 #include "error.h"
-#include "machreg.h"
-#include "dinit.h"
-#include "cg.h"
-#include "mach.h"
+#include "exp_rte.h"
+#include "expand.h"
 #include "fih.h"
-#include "pd.h"
-#include "llutil.h"
-#include "lldebug.h"
 #include "go.h"
-#include "sharedefs.h"
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#include "llassem.h"
+#include "ll_ftn.h"
 #include "ll_write.h"
-#include "expand.h"
-#include "outliner.h"
+#include "llassem.h"
+#include "lldebug.h"
+#include "llutil.h"
+#include "mach.h"
+#include "machreg.h"
 #include "mth.h"
+#include "outliner.h"
+#include "pd.h"
+#include "sharedefs.h"
 #if defined(SOCPTRG)
 #include "soc.h"
 #endif
@@ -2643,7 +2644,8 @@ get_omnipotent_pointer(LL_Module *module)
     const char *baseName = "Flang FAA";
     const char *const omniName = "unlimited ptr";
     const char *const unObjName = "unref ptr";
-    snprintf(baseBuff, 32, "%s %x", baseName, funcId);
+    snprintf(baseBuff, 32, "%s %zx %x", baseName,
+             std::hash<std::string>{}(current_module->module_name), funcId);
     s0 = ll_get_md_string(module, baseBuff);
     r0 = ll_get_md_node(module, LL_PlainMDNode, &s0, 1);
     a[0] = ll_get_md_string(module, unObjName);