llvm-6502/test/CodeGen/X86/mul128_sext_loop.ll
Manuel Jacob f8909fa140 CodeGenPrep: sink extends of illegal types into use block.
Summary:
This helps the instruction selector to lower an i64 * i64 -> i128
multiplication into a single instruction on targets which support it.

This is an update of D2973 which was reverted because of a bug reported
as PR19084.

Reviewers: t.p.northover, chapuni

Reviewed By: t.p.northover

CC: llvm-commits, alex, chapuni

Differential Revision: http://llvm-reviews.chandlerc.com/D3021

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203797 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-13 13:36:25 +00:00

33 lines
1.0 KiB
LLVM

; RUN: llc < %s -march=x86-64 | FileCheck %s
define void @test(i64* nocapture %arr, i64 %arrsize, i64 %factor) nounwind uwtable {
%1 = icmp sgt i64 %arrsize, 0
br i1 %1, label %.lr.ph, label %._crit_edge
.lr.ph: ; preds = %0
%2 = sext i64 %factor to i128
br label %3
; <label>:3 ; preds = %3, %.lr.ph
; CHECK-NOT: mul
; CHECK: imulq
; CHECK-NOT: mul
%carry.02 = phi i128 [ 0, %.lr.ph ], [ %10, %3 ]
%i.01 = phi i64 [ 0, %.lr.ph ], [ %11, %3 ]
%4 = getelementptr inbounds i64* %arr, i64 %i.01
%5 = load i64* %4, align 8
%6 = sext i64 %5 to i128
%7 = mul nsw i128 %6, %2
%8 = add nsw i128 %7, %carry.02
%.tr = trunc i128 %8 to i64
%9 = and i64 %.tr, 9223372036854775807
store i64 %9, i64* %4, align 8
%10 = ashr i128 %8, 63
%11 = add nsw i64 %i.01, 1
%exitcond = icmp eq i64 %11, %arrsize
br i1 %exitcond, label %._crit_edge, label %3
._crit_edge: ; preds = %3, %0
ret void
}