Zero-initialize stack pointers

ollef · May 31, 2024 · 1002c1a · 1002c1a
1 parent 5950442
commit 1002c1a
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/src/LowToLLVM.hs b/src/LowToLLVM.hs
@@ -431,6 +431,15 @@ assembleTerm env nameSuggestion passBy = \case
       varName bytes <> " = add i32 " <> varName pointerBytes <> ", " <> varName nonPointerBytes
     allocaBytes <- freshVar "alloca_bytes"
     emitInstruction $ varName allocaBytes <> " = alloca i8, i32 " <> varName bytes
+    declareLLVMGlobal "llvm.memset.p0.i32" "declare void @llvm.memset.p0.i32(ptr, i8, i32, i1)"
+    emitInstruction $
+      "call void @llvm.memset.p0.i32"
+        <> parens
+          [ "ptr " <> varName allocaBytes
+          , "i8 0" -- val
+          , "i32 " <> varName pointerBytes
+          , "i1 0" -- isvolatile
+          ]
     nonPointerPointer <- freshVar "non_pointer_pointer"
     emitInstruction $
       varName nonPointerPointer