diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/codeGen/StgCmmPrim.hs | 3 | ||||
| -rw-r--r-- | compiler/llvmGen/LlvmCodeGen/CodeGen.hs | 34 |
2 files changed, 36 insertions, 1 deletions
diff --git a/compiler/codeGen/StgCmmPrim.hs b/compiler/codeGen/StgCmmPrim.hs index 563f6dcc4a..243e2a32ac 100644 --- a/compiler/codeGen/StgCmmPrim.hs +++ b/compiler/codeGen/StgCmmPrim.hs @@ -823,7 +823,8 @@ callishPrimOpSupported dflags op || llvm -> Left (MO_SubIntC (wordWidth dflags)) | otherwise -> Right genericIntSubCOp - WordMul2Op | ncg && x86ish -> Left (MO_U_Mul2 (wordWidth dflags)) + WordMul2Op | ncg && x86ish + || llvm -> Left (MO_U_Mul2 (wordWidth dflags)) | otherwise -> Right genericWordMul2Op _ -> pprPanic "emitPrimOp: can't translate PrimOp " (ppr op) diff --git a/compiler/llvmGen/LlvmCodeGen/CodeGen.hs b/compiler/llvmGen/LlvmCodeGen/CodeGen.hs index 15350bca7d..fb02120747 100644 --- a/compiler/llvmGen/LlvmCodeGen/CodeGen.hs +++ b/compiler/llvmGen/LlvmCodeGen/CodeGen.hs @@ -256,6 +256,38 @@ genCall t@(PrimTarget op) [] args `appOL` stmts4 `snocOL` call return (stmts, top1 ++ top2) +-- We handle MO_U_Mul2 by simply using a 'mul' instruction, but with operands +-- twice the width (we first zero-extend them), e.g., on 64-bit arch we will +-- generate 'mul' on 128-bit operands. Then we only need some plumbing to +-- extract the two 64-bit values out of 128-bit result. +genCall (PrimTarget (MO_U_Mul2 w)) [dstH, dstL] [lhs, rhs] = do + let width = widthToLlvmInt w + bitWidth = widthInBits w + width2x = LMInt (bitWidth * 2) + -- First zero-extend the operands ('mul' instruction requires the operands + -- and the result to be of the same type). Note that we don't use 'castVars' + -- because it tries to do LM_Sext. + (lhsVar, stmts1, decls1) <- exprToVar lhs + (rhsVar, stmts2, decls2) <- exprToVar rhs + (lhsExt, stmt3) <- doExpr width2x $ Cast LM_Zext lhsVar width2x + (rhsExt, stmt4) <- doExpr width2x $ Cast LM_Zext rhsVar width2x + -- Do the actual multiplication (note that the result is also 2x width). + (retV, stmt5) <- doExpr width2x $ LlvmOp LM_MO_Mul lhsExt rhsExt + -- Extract the lower bits of the result into retL. + (retL, stmt6) <- doExpr width $ Cast LM_Trunc retV width + -- Now we right-shift the higher bits by width. + let widthLlvmLit = LMLitVar $ LMIntLit (fromIntegral bitWidth) width + (retShifted, stmt7) <- doExpr width2x $ LlvmOp LM_MO_LShr retV widthLlvmLit + -- And extract them into retH. + (retH, stmt8) <- doExpr width $ Cast LM_Trunc retShifted width + dstRegL <- getCmmReg (CmmLocal dstL) + dstRegH <- getCmmReg (CmmLocal dstH) + let storeL = Store retL dstRegL + storeH = Store retH dstRegH + stmts = stmts1 `appOL` stmts2 `appOL` + toOL [ stmt3 , stmt4, stmt5, stmt6, stmt7, stmt8, storeL, storeH ] + return (stmts, decls1 ++ decls2) + -- Handle the MO_{Add,Sub}IntC separately. LLVM versions return a record from -- which we need to extract the actual values. genCall t@(PrimTarget (MO_AddIntC w)) [dstV, dstO] [lhs, rhs] = @@ -621,6 +653,8 @@ cmmPrimOpFunctions mop = do MO_S_QuotRem {} -> unsupported MO_U_QuotRem {} -> unsupported MO_U_QuotRem2 {} -> unsupported + -- We support MO_U_Mul2 through ordinary LLVM mul instruction, see the + -- appropriate case of genCall. MO_U_Mul2 {} -> unsupported MO_WriteBarrier -> unsupported MO_Touch -> unsupported |