[StackCheck] Handle colliding names (#3390)

Add Names::getValidGlobalName calls to ensure we don't collide with an existing name.

Fixes emscripten-core/emscripten#12834

2 files changed, 32 insertions, 0 deletions

diff --git a/test/passes/stack-check_enable-mutable-globals.txt b/test/passes/stack-check_enable-mutable-globals.txt
index c89f112a8..3f8aa4da7 100644
--- a/test/passes/stack-check_enable-mutable-globals.txt
+++ b/test/passes/stack-check_enable-mutable-globals.txt
@@ -39,3 +39,25 @@
   )
  )
 )
+(module
+ (type $i32_i32_=>_none (func (param i32 i32)))
+ (type $none_=>_i32 (func (result i32)))
+ (import "env" "__stack_pointer" (global $sp (mut i32)))
+ (global $__stack_base (mut i32) (i32.const 0))
+ (global $__stack_limit (mut i32) (i32.const 0))
+ (global $__stack_base_0 (mut i32) (i32.const 0))
+ (global $__stack_limit_0 (mut i32) (i32.const 0))
+ (export "use_stack" (func $0))
+ (export "__set_stack_limits" (func $__set_stack_limits))
+ (func $0 (result i32)
+  (unreachable)
+ )
+ (func $__set_stack_limits (param $0 i32) (param $1 i32)
+  (global.set $__stack_base_0
+   (local.get $0)
+  )
+  (global.set $__stack_limit_0
+   (local.get $1)
+  )
+ )
+)
diff --git a/test/passes/stack-check_enable-mutable-globals.wast b/test/passes/stack-check_enable-mutable-globals.wast
index 3028039fd..c3583cd2c 100644
--- a/test/passes/stack-check_enable-mutable-globals.wast
+++ b/test/passes/stack-check_enable-mutable-globals.wast
@@ -5,3 +5,13 @@
   (global.get $sp)
  )
 )
+;; if the global names are taken we should not crash
+(module
+ (import "env" "__stack_pointer" (global $sp (mut i32)))
+ (global $__stack_base (mut i32) (i32.const 0))
+ (global $__stack_limit (mut i32) (i32.const 0))
+ (export "use_stack" (func $0))
+ (func $0 (result i32)
+  (unreachable)
+ )
+)