mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-01-23 02:32:11 +00:00
4015c5e2e4
Summary:
nsw are flaky and can often be removed by optimizations. This patch enhances
nsw by leveraging @llvm.assume in the IR. Specifically, NaryReassociate now
understands that
assume(a + b >= 0) && assume(a >= 0) ==> a +nsw b
As a result, it can split more sext(a + b) into sext(a) + sext(b) for CSE.
Test Plan: nary-gep.ll
Reviewers: broune, meheff
Subscribers: jholewinski, llvm-commits
Differential Revision: http://reviews.llvm.org/D10822
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241139 91177308-0d34-0410-b5e6-96231b3b80d8
127 lines
3.8 KiB
LLVM
127 lines
3.8 KiB
LLVM
; RUN: opt < %s -nary-reassociate -early-cse -S | FileCheck %s
|
|
|
|
target datalayout = "e-i64:64-v16:16-v32:32-n16:32:64"
|
|
target triple = "nvptx64-unknown-unknown"
|
|
|
|
declare void @foo(float*)
|
|
|
|
; foo(&a[i]);
|
|
; foo(&a[i + j]);
|
|
; =>
|
|
; t = &a[i];
|
|
; foo(t);
|
|
; foo(t + j);
|
|
define void @reassociate_gep(float* %a, i64 %i, i64 %j) {
|
|
; CHECK-LABEL: @reassociate_gep(
|
|
%1 = add i64 %i, %j
|
|
%2 = getelementptr float, float* %a, i64 %i
|
|
; CHECK: [[t1:[^ ]+]] = getelementptr float, float* %a, i64 %i
|
|
call void @foo(float* %2)
|
|
; CHECK: call void @foo(float* [[t1]])
|
|
%3 = getelementptr float, float* %a, i64 %1
|
|
; CHECK: [[t2:[^ ]+]] = getelementptr float, float* [[t1]], i64 %j
|
|
call void @foo(float* %3)
|
|
; CHECK: call void @foo(float* [[t2]])
|
|
ret void
|
|
}
|
|
|
|
; foo(&a[sext(j)]);
|
|
; foo(&a[sext(i +nsw j)]);
|
|
; foo(&a[sext((i +nsw j) +nsw i)]);
|
|
; =>
|
|
; t1 = &a[sext(j)];
|
|
; foo(t1);
|
|
; t2 = t1 + sext(i);
|
|
; foo(t2);
|
|
; t3 = t2 + sext(i); // sext(i) should be GVN'ed.
|
|
; foo(t3);
|
|
define void @reassociate_gep_nsw(float* %a, i32 %i, i32 %j) {
|
|
; CHECK-LABEL: @reassociate_gep_nsw(
|
|
%idxprom.j = sext i32 %j to i64
|
|
%1 = getelementptr float, float* %a, i64 %idxprom.j
|
|
; CHECK: [[t1:[^ ]+]] = getelementptr float, float* %a, i64 %idxprom.j
|
|
call void @foo(float* %1)
|
|
; CHECK: call void @foo(float* [[t1]])
|
|
|
|
%2 = add nsw i32 %i, %j
|
|
%idxprom.2 = sext i32 %2 to i64
|
|
%3 = getelementptr float, float* %a, i64 %idxprom.2
|
|
; CHECK: [[sexti:[^ ]+]] = sext i32 %i to i64
|
|
; CHECK: [[t2:[^ ]+]] = getelementptr float, float* [[t1]], i64 [[sexti]]
|
|
call void @foo(float* %3)
|
|
; CHECK: call void @foo(float* [[t2]])
|
|
|
|
%4 = add nsw i32 %2, %i
|
|
%idxprom.4 = sext i32 %4 to i64
|
|
%5 = getelementptr float, float* %a, i64 %idxprom.4
|
|
; CHECK: [[t3:[^ ]+]] = getelementptr float, float* [[t2]], i64 [[sexti]]
|
|
call void @foo(float* %5)
|
|
; CHECK: call void @foo(float* [[t3]])
|
|
|
|
ret void
|
|
}
|
|
|
|
; assume(j >= 0);
|
|
; foo(&a[zext(j)]);
|
|
; assume(i + j >= 0);
|
|
; foo(&a[zext(i + j)]);
|
|
; =>
|
|
; t1 = &a[zext(j)];
|
|
; foo(t1);
|
|
; t2 = t1 + sext(i);
|
|
; foo(t2);
|
|
define void @reassociate_gep_assume(float* %a, i32 %i, i32 %j) {
|
|
; CHECK-LABEL: @reassociate_gep_assume(
|
|
; assume(j >= 0)
|
|
%cmp = icmp sgt i32 %j, -1
|
|
call void @llvm.assume(i1 %cmp)
|
|
%1 = add i32 %i, %j
|
|
%cmp2 = icmp sgt i32 %1, -1
|
|
call void @llvm.assume(i1 %cmp2)
|
|
|
|
%idxprom.j = zext i32 %j to i64
|
|
%2 = getelementptr float, float* %a, i64 %idxprom.j
|
|
; CHECK: [[t1:[^ ]+]] = getelementptr float, float* %a, i64 %idxprom.j
|
|
call void @foo(float* %2)
|
|
; CHECK: call void @foo(float* [[t1]])
|
|
|
|
%idxprom.1 = zext i32 %1 to i64
|
|
%3 = getelementptr float, float* %a, i64 %idxprom.1
|
|
; CHECK: [[sexti:[^ ]+]] = sext i32 %i to i64
|
|
; CHECK: [[t2:[^ ]+]] = getelementptr float, float* [[t1]], i64 [[sexti]]
|
|
call void @foo(float* %3)
|
|
; CHECK: call void @foo(float* [[t2]])
|
|
|
|
ret void
|
|
}
|
|
|
|
; Do not split the second GEP because sext(i + j) != sext(i) + sext(j).
|
|
define void @reassociate_gep_no_nsw(float* %a, i32 %i, i32 %j) {
|
|
; CHECK-LABEL: @reassociate_gep_no_nsw(
|
|
%1 = add i32 %i, %j
|
|
%2 = getelementptr float, float* %a, i32 %j
|
|
; CHECK: getelementptr float, float* %a, i32 %j
|
|
call void @foo(float* %2)
|
|
%3 = getelementptr float, float* %a, i32 %1
|
|
; CHECK: getelementptr float, float* %a, i32 %1
|
|
call void @foo(float* %3)
|
|
ret void
|
|
}
|
|
|
|
define void @reassociate_gep_128(float* %a, i128 %i, i128 %j) {
|
|
; CHECK-LABEL: @reassociate_gep_128(
|
|
%1 = add i128 %i, %j
|
|
%2 = getelementptr float, float* %a, i128 %i
|
|
; CHECK: [[t1:[^ ]+]] = getelementptr float, float* %a, i128 %i
|
|
call void @foo(float* %2)
|
|
; CHECK: call void @foo(float* [[t1]])
|
|
%3 = getelementptr float, float* %a, i128 %1
|
|
; CHECK: [[truncj:[^ ]+]] = trunc i128 %j to i64
|
|
; CHECK: [[t2:[^ ]+]] = getelementptr float, float* [[t1]], i64 [[truncj]]
|
|
call void @foo(float* %3)
|
|
; CHECK: call void @foo(float* [[t2]])
|
|
ret void
|
|
}
|
|
|
|
declare void @llvm.assume(i1)
|