LLVM: Use the inbounds keyword for getelementptr instructions.

compiler/llvmGen/Llvm/AbsSyn.hs

@@ -171,12 +171,13 @@ data LlvmExpression
 
   {- |
     Navigate in an structure, selecting elements
+      * inbound: Is the pointer inbounds? (computed pointer doesn't overflow)
       * ptr:     Location of the structure
       * indexes: A list of indexes to select the correct value. For example
                  the first element of the third element of the structure ptr
                  is selected with [3,1] (zero indexed)
   -}
-  | GetElemPtr LlvmVar [Int]
+  | GetElemPtr Bool LlvmVar [Int]
 
   {- |
      Cast the variable from to the to type. This is an abstraction of three

compiler/llvmGen/Llvm/PpLlvm.hs

@@ -177,7 +177,7 @@ ppLlvmExpression expr
         Call       tp fp args attrs -> ppCall tp fp args attrs
         Cast       op from to       -> ppCast op from to
         Compare    op left right    -> ppCmpOp op left right
-        GetElemPtr ptr indexes      -> ppGetElementPtr ptr indexes
+        GetElemPtr inb ptr indexes  -> ppGetElementPtr inb ptr indexes
         Load       ptr              -> ppLoad ptr
         Malloc     tp amount        -> ppMalloc tp amount
         Phi        tp precessors    -> ppPhi tp precessors
@@ -268,10 +268,11 @@ ppAlloca tp amount =
   in text "alloca" <+> texts tp <> comma <+> texts amount'
 
 
-ppGetElementPtr :: LlvmVar -> [Int] -> Doc
-ppGetElementPtr ptr idx =
+ppGetElementPtr :: Bool -> LlvmVar -> [Int] -> Doc
+ppGetElementPtr inb ptr idx =
   let indexes = hcat $ map ((comma <+> texts i32 <+>) . texts) idx
-  in text "getelementptr" <+> texts ptr <> indexes
+      inbound = if inb then text "inbounds" else empty
+  in text "getelementptr" <+> inbound <+> texts ptr <> indexes
 
 
 ppReturn :: Maybe LlvmVar -> Doc

compiler/llvmGen/LlvmCodeGen/CodeGen.hs

@@ -482,7 +482,7 @@ genStore_fast env addr r n val
             True -> do
                 (env', vval,  stmts, top) <- exprToVar env val
                 (gv,  s1) <- doExpr grt $ Load gr
-                (ptr, s2) <- doExpr grt $ GetElemPtr gv [ix]
+                (ptr, s2) <- doExpr grt $ GetElemPtr True gv [ix]
                 -- We might need a different pointer type, so check
                 case pLower grt == getVarType vval of
                      -- were fine
@@ -722,7 +722,7 @@ genMachOp_fast env opt op r n e
     in case isPointer grt && rem == 0 of
             True -> do
                 (gv,  s1) <- doExpr grt $ Load gr
-                (ptr, s2) <- doExpr grt $ GetElemPtr gv [ix]
+                (ptr, s2) <- doExpr grt $ GetElemPtr True gv [ix]
                 (var, s3) <- doExpr llvmWord $ Cast LM_Ptrtoint ptr llvmWord
                 return (env, var, unitOL s1 `snocOL` s2 `snocOL` s3, [])
 
@@ -920,7 +920,7 @@ genLoad_fast env e r n ty =
     in case isPointer grt && rem == 0 of
             True  -> do
                 (gv,  s1) <- doExpr grt $ Load gr
-                (ptr, s2) <- doExpr grt $ GetElemPtr gv [ix]
+                (ptr, s2) <- doExpr grt $ GetElemPtr True gv [ix]
                 -- We might need a different pointer type, so check
                 case grt == ty' of
                      -- were fine