Change memory indexing to use the type as index instead of i8, also add nsw/nuw flags whenever possible.

Author: gbaraldi

src/cgutils.cpp

@@ -2053,7 +2053,7 @@ static bool bounds_check_enabled(jl_codectx_t &ctx, jl_value_t *inbounds) {
 
 static Value *emit_bounds_check(jl_codectx_t &ctx, const jl_cgval_t &ainfo, jl_value_t *ty, Value *i, Value *len, jl_value_t *boundscheck)
 {
-    Value *im1 = ctx.builder.CreateSub(i, ConstantInt::get(ctx.types().T_size, 1));
+    Value *im1 = ctx.builder.CreateSub(i, ConstantInt::get(ctx.types().T_size, 1)); // Can this be nuw/nsw
     if (bounds_check_enabled(ctx, boundscheck)) {
         ++EmittedBoundschecks;
         Value *ok = ctx.builder.CreateICmpULT(im1, len);
@@ -4659,7 +4659,7 @@ static jl_cgval_t emit_memoryref(jl_codectx_t &ctx, const jl_cgval_t &ref, jl_cg
     Value *mem = CreateSimplifiedExtractValue(ctx, V, 1);
     maybeSetName(ctx.emission_context, mem, "memoryref_mem");
     Value *i = emit_unbox(ctx, ctx.types().T_size, idx, (jl_value_t*)jl_long_type);
-    Value *offset = ctx.builder.CreateSub(i, ConstantInt::get(ctx.types().T_size, 1));
+    Value *offset = ctx.builder.CreateSub(i, ConstantInt::get(ctx.types().T_size, 1), "", true, true);
     setName(ctx.emission_context, offset, "memoryref_offset");
     Value *elsz = emit_genericmemoryelsize(ctx, mem, ref.typ, false);
     bool bc = bounds_check_enabled(ctx, inbounds);
@@ -4671,7 +4671,7 @@ static jl_cgval_t emit_memoryref(jl_codectx_t &ctx, const jl_cgval_t &ref, jl_cg
     bool isunion = layout->flags.arrayelem_isunion;
     bool isghost = layout->size == 0;
     if ((!isboxed && isunion) || isghost) {
-        newdata = ctx.builder.CreateAdd(data, offset);
+        newdata = ctx.builder.CreateAdd(data, offset, "", true, true);
         setName(ctx.emission_context, newdata, "memoryref_data+offset");
         if (bc) {
             BasicBlock *failBB, *endBB;
@@ -4710,10 +4710,9 @@ static jl_cgval_t emit_memoryref(jl_codectx_t &ctx, const jl_cgval_t &ref, jl_cg
             setName(ctx.emission_context, ovflw, "memoryref_ovflw");
         }
 #endif
-        boffset = ctx.builder.CreateMul(offset, elsz);
-        setName(ctx.emission_context, boffset, "memoryref_byteoffset");
-        newdata = ctx.builder.CreateGEP(getInt8Ty(ctx.builder.getContext()), data, boffset);
-        setName(ctx.emission_context, newdata, "memoryref_data_byteoffset");
+        Type *elty = isboxed ? ctx.types().T_prjlvalue : julia_type_to_llvm(ctx, jl_tparam1(ref.typ));
+        newdata = ctx.builder.CreateInBoundsGEP(elty, data, offset);
+        setName(ctx.emission_context, newdata, "memoryref_data_offset");
         (void)boffset; // LLVM is very bad at handling GEP with types different from the load
         if (bc) {
             BasicBlock *failBB, *endBB;
@@ -4734,7 +4733,7 @@ static jl_cgval_t emit_memoryref(jl_codectx_t &ctx, const jl_cgval_t &ref, jl_cg
 #elif 1
             Value *bidx0 = ctx.builder.CreateSub(
                 ctx.builder.CreatePtrToInt(newdata, ctx.types().T_size),
-                ctx.builder.CreatePtrToInt(mptr, ctx.types().T_size));
+                ctx.builder.CreatePtrToInt(mptr, ctx.types().T_size), "", true, true);
             Value *blen = ctx.builder.CreateMul(mlen, elsz, "", true, true);
             setName(ctx.emission_context, blen, "memoryref_bytelen");
             Value *inbound = ctx.builder.CreateICmpULT(bidx0, blen);
@@ -4776,13 +4775,13 @@ static jl_cgval_t emit_memoryref_offset(jl_codectx_t &ctx, const jl_cgval_t &ref
         // (data - mptr) / elsz
         offset = ctx.builder.CreateSub(
             ctx.builder.CreatePtrToInt(data, ctx.types().T_size),
-            ctx.builder.CreatePtrToInt(mptr, ctx.types().T_size));
+            ctx.builder.CreatePtrToInt(mptr, ctx.types().T_size), "", true, true);
         setName(ctx.emission_context, offset, "memoryref_offset");
         Value *elsz = emit_genericmemoryelsize(ctx, mem, ref.typ, false);
         offset = ctx.builder.CreateExactUDiv(offset, elsz);
         setName(ctx.emission_context, offset, "memoryref_offsetidx");
     }
-    offset = ctx.builder.CreateAdd(offset, ConstantInt::get(ctx.types().T_size, 1));
+    offset = ctx.builder.CreateAdd(offset, ConstantInt::get(ctx.types().T_size, 1), "", true, true);
     return mark_julia_type(ctx, offset, false, jl_long_type);
 }
 

src/codegen.cpp

@@ -4870,7 +4870,7 @@ static bool emit_builtin_call(jl_codectx_t &ctx, jl_cgval_t *ret, jl_value_t *f,
                     // This is not necessary for correctness, but allows to omit
                     // the extra code for getting the length of the tuple
                     if (!bounds_check_enabled(ctx, boundscheck)) {
-                        vidx = ctx.builder.CreateSub(vidx, ConstantInt::get(ctx.types().T_size, 1));
+                        vidx = ctx.builder.CreateSub(vidx, ConstantInt::get(ctx.types().T_size, 1), "", true, true);
                     }
                     else {
                         vidx = emit_bounds_check(ctx, ptrobj, (jl_value_t*)ptrobj.typ, vidx,