Index: llvm/trunk/lib/Analysis/ScalarEvolution.cpp =================================================================== --- llvm/trunk/lib/Analysis/ScalarEvolution.cpp +++ llvm/trunk/lib/Analysis/ScalarEvolution.cpp @@ -121,6 +121,11 @@ cl::desc("Verify no dangling value in ScalarEvolution's " "ExprValueMap (slow)")); +static cl::opt MulOpsInlineThreshold( + "scev-mulops-inline-threshold", cl::Hidden, + cl::desc("Threshold for inlining multiplication operands into a SCEV"), + cl::init(1000)); + //===----------------------------------------------------------------------===// // SCEV class definitions //===----------------------------------------------------------------------===// @@ -2516,6 +2521,8 @@ if (Idx < Ops.size()) { bool DeletedMul = false; while (const SCEVMulExpr *Mul = dyn_cast(Ops[Idx])) { + if (Ops.size() > MulOpsInlineThreshold) + break; // If we have an mul, expand the mul operands onto the end of the operands // list. Ops.erase(Ops.begin()+Idx); Index: llvm/trunk/test/Analysis/ScalarEvolution/max-mulops-inline.ll =================================================================== --- llvm/trunk/test/Analysis/ScalarEvolution/max-mulops-inline.ll +++ llvm/trunk/test/Analysis/ScalarEvolution/max-mulops-inline.ll @@ -0,0 +1,29 @@ +; RUN: opt -analyze -scalar-evolution -scev-mulops-inline-threshold=1 < %s | FileCheck --check-prefix=CHECK1 %s +; RUN: opt -analyze -scalar-evolution -scev-mulops-inline-threshold=10 < %s | FileCheck --check-prefix=CHECK10 %s + +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +@a = local_unnamed_addr global i32 0, align 4 +@b = local_unnamed_addr global i32 0, align 4 + +define i32 @main() local_unnamed_addr { + +; CHECK1: %mul.1 = mul nsw i32 %mul, %mul +; CHECK1: --> ((%a.promoted * %a.promoted) * (%a.promoted * %a.promoted)) + +; CHECK10: %mul.1 = mul nsw i32 %mul, %mul +; CHECK10: --> (%a.promoted * %a.promoted * %a.promoted * %a.promoted) + +entry: + %a.promoted = load i32, i32* @a, align 4 + %mul = mul nsw i32 %a.promoted, %a.promoted + %mul.1 = mul nsw i32 %mul, %mul + %mul.2 = mul nsw i32 %mul.1, %mul.1 + %mul.3 = mul nsw i32 %mul.2, %mul.2 + %mul.4 = mul nsw i32 %mul.3, %mul.3 + %mul.5 = mul nsw i32 %mul.4, %mul.4 + store i32 %mul.5, i32* @a, align 4 + store i32 31, i32* @b, align 4 + ret i32 0 +}