[llvm] ac4896e - [GlobalISel] Add G_ROTL and G_ROTR to right_identity_zero
Jessica Paquette via llvm-commits
llvm-commits at lists.llvm.org
Wed Sep 8 10:09:33 PDT 2021
Author: Jessica Paquette
Date: 2021-09-08T10:09:02-07:00
New Revision: ac4896e2f37296ef47aa6f03723d275de23180f7
URL: https://github.com/llvm/llvm-project/commit/ac4896e2f37296ef47aa6f03723d275de23180f7
DIFF: https://github.com/llvm/llvm-project/commit/ac4896e2f37296ef47aa6f03723d275de23180f7.diff
LOG: [GlobalISel] Add G_ROTL and G_ROTR to right_identity_zero
Similar to `DAGCombiner::visitRotate`.
This makes `rotl_bitwidth_cst` in postlegalizercombiner-rotate.mir reduce down
to a COPY. Modify the checkline to make sure that only rotate_out_of_range
runs there.
Differential Revision: https://reviews.llvm.org/D109264
Added:
Modified:
llvm/include/llvm/Target/GlobalISel/Combine.td
llvm/test/CodeGen/AArch64/GlobalISel/postlegalizercombiner-rotate.mir
llvm/test/CodeGen/AArch64/GlobalISel/prelegalizercombiner-trivial-arith.mir
Removed:
################################################################################
diff --git a/llvm/include/llvm/Target/GlobalISel/Combine.td b/llvm/include/llvm/Target/GlobalISel/Combine.td
index 1808aa6e6e66a..519edbe043de8 100644
--- a/llvm/include/llvm/Target/GlobalISel/Combine.td
+++ b/llvm/include/llvm/Target/GlobalISel/Combine.td
@@ -281,7 +281,7 @@ def select_constant_cmp: GICombineRule<
def right_identity_zero: GICombineRule<
(defs root:$root),
(match (wip_match_opcode G_SUB, G_ADD, G_OR, G_XOR, G_SHL, G_ASHR, G_LSHR,
- G_PTR_ADD):$root,
+ G_PTR_ADD, G_ROTL, G_ROTR):$root,
[{ return Helper.matchConstantOp(${root}->getOperand(2), 0); }]),
(apply [{ return Helper.replaceSingleDefInstWithOperand(*${root}, 1); }])
>;
diff --git a/llvm/test/CodeGen/AArch64/GlobalISel/postlegalizercombiner-rotate.mir b/llvm/test/CodeGen/AArch64/GlobalISel/postlegalizercombiner-rotate.mir
index eef80e054dcd4..6a130a2192ab4 100644
--- a/llvm/test/CodeGen/AArch64/GlobalISel/postlegalizercombiner-rotate.mir
+++ b/llvm/test/CodeGen/AArch64/GlobalISel/postlegalizercombiner-rotate.mir
@@ -1,5 +1,6 @@
# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
-# RUN: llc -mtriple aarch64 -run-pass=aarch64-postlegalizer-combiner -verify-machineinstrs %s -o - | FileCheck %s
+# RUN: llc -mtriple aarch64 -run-pass=aarch64-postlegalizer-combiner --aarch64postlegalizercombinerhelper-only-enable-rule="rotate_out_of_range" -verify-machineinstrs %s -o - | FileCheck %s
+# REQUIRES: asserts
# Check that we simplify the constant rotate amount to be in range.
---
diff --git a/llvm/test/CodeGen/AArch64/GlobalISel/prelegalizercombiner-trivial-arith.mir b/llvm/test/CodeGen/AArch64/GlobalISel/prelegalizercombiner-trivial-arith.mir
index 55e63ba01d35e..9551526e1fce1 100644
--- a/llvm/test/CodeGen/AArch64/GlobalISel/prelegalizercombiner-trivial-arith.mir
+++ b/llvm/test/CodeGen/AArch64/GlobalISel/prelegalizercombiner-trivial-arith.mir
@@ -325,3 +325,39 @@ body: |
%op:_(p0) = G_PTR_ADD %x(p0), %cst
$x0 = COPY %op(p0)
RET_ReallyLR implicit $x0
+...
+---
+name: right_identity_rotl
+tracksRegLiveness: true
+body: |
+ bb.0:
+ liveins: $w0, $w1
+ ; CHECK-LABEL: name: right_identity_rotl
+ ; CHECK: liveins: $w0, $w1
+ ; CHECK: %copy:_(s32) = COPY $w0
+ ; CHECK: $w0 = COPY %copy(s32)
+ ; CHECK: RET_ReallyLR implicit $w0
+ %copy:_(s32) = COPY $w0
+ %zero:_(s32) = G_CONSTANT i32 0
+ %rot:_(s32) = G_ROTL %copy(s32), %zero(s32)
+ $w0 = COPY %rot(s32)
+ RET_ReallyLR implicit $w0
+...
+...
+---
+name: right_identity_rotr
+tracksRegLiveness: true
+body: |
+ bb.0:
+ liveins: $w0, $w1
+ ; CHECK-LABEL: name: right_identity_rotr
+ ; CHECK: liveins: $w0, $w1
+ ; CHECK: %copy:_(s32) = COPY $w0
+ ; CHECK: $w0 = COPY %copy(s32)
+ ; CHECK: RET_ReallyLR implicit $w0
+ %copy:_(s32) = COPY $w0
+ %zero:_(s32) = G_CONSTANT i32 0
+ %rot:_(s32) = G_ROTR %copy(s32), %zero(s32)
+ $w0 = COPY %rot(s32)
+ RET_ReallyLR implicit $w0
+...
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