From f237d85af063b56f01c60b7720baa9c89b3ef413 Mon Sep 17 00:00:00 2001
From: Alexey Prokhin <alexey.prokhin@yandex.ru>
Date: Sat, 4 Feb 2012 19:33:55 +0400
Subject: [PATCH] Implemented bt/btc/btr/bts intrinsics

---
 gen/pragma.cpp   | 37 ++++++++++++++++++++++++++++++++++
 gen/pragma.h     |  6 +++++-
 gen/toir.cpp     | 52 ++++++++++++++++++++++++++++++++++++++++++++++++
 runtime/druntime |  2 +-
 4 files changed, 95 insertions(+), 2 deletions(-)

diff --git a/gen/pragma.cpp b/gen/pragma.cpp
index aacd5abe..d10f3fc9 100644
--- a/gen/pragma.cpp
+++ b/gen/pragma.cpp
@@ -30,6 +30,18 @@ Pragma DtoGetPragma(Scope *sc, PragmaDeclaration *decl, std::string &arg1str)
     // pragma(intrinsic, "string") { funcdecl(s) }
     if (ident == Id::intrinsic)
     {
+        struct LdcIntrinsic
+        {
+            std::string name;
+            Pragma pragma;
+        };
+        static LdcIntrinsic ldcIntrinsic[] = {
+            { "bitop.bt",  LLVMbitop_bt },
+            { "bitop.btc", LLVMbitop_btc },
+            { "bitop.btr", LLVMbitop_btr },
+            { "bitop.bts", LLVMbitop_bts },
+        };
+
         Expression* expr = (Expression *)args->data[0];
         expr = expr->semantic(sc);
         if (!args || args->dim != 1 || !parseStringExp(expr, arg1str))
@@ -37,6 +49,27 @@ Pragma DtoGetPragma(Scope *sc, PragmaDeclaration *decl, std::string &arg1str)
              error("requires exactly 1 string literal parameter");
              fatal();
         }
+
+        std::string prefix = "ldc.";
+        if (arg1str.length() > prefix.length() &&
+            std::equal(prefix.begin(), prefix.end(), arg1str.begin()))
+        {
+            std::string name(arg1str.begin() + prefix.length(), arg1str.end());
+            int i = 0, j = sizeof(ldcIntrinsic) / sizeof(ldcIntrinsic[0]), k, l;
+            do
+            {
+                k = (i + j) / 2;
+                l = name.compare(ldcIntrinsic[k].name);
+                if (!l)
+                    return ldcIntrinsic[k].pragma;
+                else if (l < 0)
+                    j = k;
+                else
+                    i = k + 1;
+            }
+            while (i != j);
+        }
+
         return LLVMintrinsic;
     }
 
@@ -292,6 +325,10 @@ void DtoCheckPragma(PragmaDeclaration *decl, Dsymbol *s,
     case LLVMva_copy:
     case LLVMva_end:
     case LLVMfence:
+    case LLVMbitop_bt:
+    case LLVMbitop_btc:
+    case LLVMbitop_btr:
+    case LLVMbitop_bts:
         if (FuncDeclaration* fd = s->isFuncDeclaration())
         {
             fd->llvmInternal = llvm_internal;
diff --git a/gen/pragma.h b/gen/pragma.h
index 90119ef0..cd53239a 100644
--- a/gen/pragma.h
+++ b/gen/pragma.h
@@ -23,7 +23,11 @@ enum Pragma
     LLVMatomic_store,
     LLVMatomic_load,
     LLVMatomic_cmp_xchg,
-    LLVMatomic_rmw
+    LLVMatomic_rmw,
+    LLVMbitop_bt,
+    LLVMbitop_btc,
+    LLVMbitop_btr,
+    LLVMbitop_bts
 };
 
 Pragma DtoGetPragma(Scope *sc, PragmaDeclaration *decl, std::string &arg1str);
diff --git a/gen/toir.cpp b/gen/toir.cpp
index cfdda25c..97caa737 100644
--- a/gen/toir.cpp
+++ b/gen/toir.cpp
@@ -1007,6 +1007,58 @@ DValue* CallExp::toElem(IRState* p)
             LLValue* ret = gIR->ir->CreateAtomicRMW(llvm::AtomicRMWInst::BinOp(op), ptr, val,
                                                     llvm::AtomicOrdering(atomicOrdering));
             return new DImValue(exp2->type, ret);
+        // bitop
+        } else if (fndecl->llvmInternal == LLVMbitop_bt ||
+                   fndecl->llvmInternal == LLVMbitop_btr ||
+                   fndecl->llvmInternal == LLVMbitop_btc ||
+                   fndecl->llvmInternal == LLVMbitop_bts)
+        {
+            if (arguments->dim != 2) {
+                error("bitop intrinsic %s expects 2 arguments");
+                return NULL;
+            }
+
+            Expression* exp1 = (Expression*)arguments->data[0];
+            Expression* exp2 = (Expression*)arguments->data[1];
+            LLValue* ptr = exp1->toElem(p)->getRVal();
+            LLValue* bitnum = exp2->toElem(p)->getRVal();
+
+            // auto q = cast(ubyte*)ptr + (bitnum >> 3);
+            LLValue* q = DtoBitCast(ptr, DtoType(Type::tuns8->pointerTo()));
+            q = DtoGEP1(q, p->ir->CreateLShr(bitnum, 3), "bitop.q");
+
+            // auto mask = 1 << (bitnum & 7);
+            LLValue* mask = p->ir->CreateAnd(bitnum, DtoConstSize_t(7), "bitop.tmp");
+            mask = p->ir->CreateShl(DtoConstSize_t(1), mask, "bitop.mask");
+
+            // auto result = (*q & mask) ? -1 : 0;
+            LLValue* val = p->ir->CreateZExt(DtoLoad(q, "bitop.tmp"), DtoSize_t(), "bitop.val");
+            LLValue* result = p->ir->CreateAnd(val, mask, "bitop.tmp");
+            result = p->ir->CreateICmpNE(result, DtoConstSize_t(0), "bitop.tmp");
+            result = p->ir->CreateSelect(result, DtoConstInt(-1), DtoConstInt(0), "bitop.result");
+
+            if (fndecl->llvmInternal != LLVMbitop_bt) {
+                llvm::Instruction::BinaryOps op;
+                if (fndecl->llvmInternal == LLVMbitop_btc) {
+                    // *q ^= mask;
+                    op = llvm::Instruction::Xor;
+                } else if (fndecl->llvmInternal == LLVMbitop_btr) {
+                    // *q &= ~mask;
+                    mask = p->ir->CreateNot(mask);
+                    op = llvm::Instruction::And;
+                } else if (fndecl->llvmInternal == LLVMbitop_bts) {
+                    // *q |= mask;
+                    op = llvm::Instruction::Or;
+                } else {
+                    assert(false);
+                }
+
+                LLValue *newVal = p->ir->CreateBinOp(op, val, mask, "bitop.new_val");
+                newVal = p->ir->CreateTrunc(newVal, DtoType(Type::tuns8), "bitop.tmp");
+                DtoStore(newVal, q);
+            }
+
+            return new DImValue(type, result);
         }
     }
     return DtoCallFunction(loc, type, fnval, arguments);
diff --git a/runtime/druntime b/runtime/druntime
index 4db79c70..33925006 160000
--- a/runtime/druntime
+++ b/runtime/druntime
@@ -1 +1 @@
-Subproject commit 4db79c70e9de8f8b3b014d6f606f10b5fc41e2c5
+Subproject commit 33925006113cb894a46c8ffcb13ddc4fd29f4c54