Use a 32-bit and with implicit zero-extension instead of a 64-bit and if it

has an immediate with at least 32 bits of leading zeros, to avoid needing to
materialize that immediate in a register first.

FileCheckize, tidy, and extend a testcase to cover this case.

This fixes rdar://7527390.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93160 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2010-01-11 17:58:34 +00:00
parent 71c25b7d7b
commit e5dacc55ad
2 changed files with 51 additions and 3 deletions

View File

@ -1966,6 +1966,17 @@ def : Pat<(add GR64:$src1, 0x0000000080000000),
def : Pat<(store (add (loadi64 addr:$dst), 0x00000000800000000), addr:$dst),
(SUB64mi32 addr:$dst, 0xffffffff80000000)>;
// Use a 32-bit and with implicit zero-extension instead of a 64-bit and if it
// has an immediate with at least 32 bits of leading zeros, to avoid needing to
// materialize that immediate in a register first.
def : Pat<(and GR64:$src, i64immZExt32:$imm),
(SUBREG_TO_REG
(i64 0),
(AND32ri
(EXTRACT_SUBREG GR64:$src, x86_subreg_32bit),
imm:$imm),
x86_subreg_32bit)>;
// r & (2^32-1) ==> movz
def : Pat<(and GR64:$src, 0x00000000FFFFFFFF),
(MOVZX64rr32 (EXTRACT_SUBREG GR64:$src, x86_subreg_32bit))>;

View File

@ -1,12 +1,49 @@
; RUN: llc < %s | grep {movl.*%edi, %eax}
; This should be a single mov, not a load of immediate + andq.
; RUN: llc < %s | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128"
target triple = "x86_64-apple-darwin8"
define i64 @test(i64 %x) nounwind {
; This should be a single mov, not a load of immediate + andq.
; CHECK: test:
; CHECK: movl %edi, %eax
define i64 @test(i64 %x) nounwind {
entry:
%tmp123 = and i64 %x, 4294967295 ; <i64> [#uses=1]
ret i64 %tmp123
}
; This copy can't be coalesced away because it needs the implicit zero-extend.
; CHECK: bbb:
; CHECK: movl %edi, %edi
define void @bbb(i64 %x) nounwind {
%t = and i64 %x, 4294967295
call void @foo(i64 %t)
ret void
}
; This should use a 32-bit and with implicit zero-extension, not a 64-bit and
; with a separate mov to materialize the mask.
; rdar://7527390
; CHECK: ccc:
; CHECK: andl $-1048593, %edi
declare void @foo(i64 %x) nounwind
define void @ccc(i64 %x) nounwind {
%t = and i64 %x, 4293918703
call void @foo(i64 %t)
ret void
}
; This requires a mov and a 64-bit and.
; CHECK: ddd:
; CHECK: movabsq $4294967296, %rax
; CHECK: andq %rax, %rdi
define void @ddd(i64 %x) nounwind {
%t = and i64 %x, 4294967296
call void @foo(i64 %t)
ret void
}