[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/Inputs/tbaa_multimod_01_input.f90

@@ -0,0 +1,22 @@
+! A part of the test provided in tbaa_multimod_01.f90
+
+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/Inputs/tbaa_multimod_02_input.f90

@@ -0,0 +1,10 @@
+! A part of the test provided in tbaa_multimod_02.f90
+
+subroutine to_load(arr)
+  implicit none
+  real, intent(inout) :: arr(:)
+  real :: var
+  var = arr(0)
+  var = var * 2
+  print var
+end subroutine to_load

test/llvm_ir_correct/tbaa_multimod_01.f90

@@ -0,0 +1,21 @@
+! This test contians two files, tbaa_multimod_01.f90 and Inputs/tbaa_multimod_01_input.f90
+! RUN: %flang -emit-llvm -c -O3 %s -o %t.bc
+! RUN: %flang -emit-llvm -c -O3 %S/Inputs/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_02.f90

@@ -0,0 +1,17 @@
+! This test contians two files, tbaa_multimod_02.f90 and Inputs/tbaa_multimod_02_input.f90
+! RUN: %flang -emit-llvm -c -O3 %s -o %t.bc
+! RUN: %flang -emit-llvm -c -O3 %S/Inputs/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

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
@@ -2639,11 +2640,12 @@ get_omnipotent_pointer(LL_Module *module)
     LL_MDRef s0;
     LL_MDRef r0;
     LL_MDRef a[3];
-    char baseBuff[32];
+    char baseBuff[64];
     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, 64, "%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);