zext-fold.ll
1.42 KB
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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=i686-unknown-linux -enable-misched=false | FileCheck %s
;; Simple case
define i32 @test1(i8 %x) nounwind readnone {
; CHECK-LABEL: test1:
; CHECK: # %bb.0:
; CHECK-NEXT: movzbl {{[0-9]+}}(%esp), %eax
; CHECK-NEXT: andl $-32, %eax
; CHECK-NEXT: retl
%A = and i8 %x, -32
%B = zext i8 %A to i32
ret i32 %B
}
;; Multiple uses of %x but easily extensible.
define i32 @test2(i8 %x) nounwind readnone {
; CHECK-LABEL: test2:
; CHECK: # %bb.0:
; CHECK-NEXT: movzbl {{[0-9]+}}(%esp), %eax
; CHECK-NEXT: movl %eax, %ecx
; CHECK-NEXT: andl $-32, %ecx
; CHECK-NEXT: orl $63, %eax
; CHECK-NEXT: addl %ecx, %eax
; CHECK-NEXT: retl
%A = and i8 %x, -32
%B = zext i8 %A to i32
%C = or i8 %x, 63
%D = zext i8 %C to i32
%E = add i32 %B, %D
ret i32 %E
}
declare void @use(i32, i8)
;; Multiple uses of %x where we shouldn't extend the load.
define void @test3(i8 %x) nounwind readnone {
; CHECK-LABEL: test3:
; CHECK: # %bb.0:
; CHECK-NEXT: subl $12, %esp
; CHECK-NEXT: movzbl {{[0-9]+}}(%esp), %eax
; CHECK-NEXT: subl $8, %esp
; CHECK-NEXT: pushl %eax
; CHECK-NEXT: andl $-32, %eax
; CHECK-NEXT: pushl %eax
; CHECK-NEXT: calll use
; CHECK-NEXT: addl $28, %esp
; CHECK-NEXT: retl
%A = and i8 %x, -32
%B = zext i8 %A to i32
call void @use(i32 %B, i8 %x)
ret void
}