mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-10-24 21:42:54 +02:00
b072cf7882
Patch by Michele Scandale! Rewrite of the functions used to compute the backedge taken count of a loop on LT and GT comparisons. I decided to split the handling of LT and GT cases becasue the trick "a > b == -a < -b" in some cases prevents the trip count computation due to the multiplication by -1 on the two operands of the comparison. This issue comes from the conservative computation of value range of SCEVs: taking the negative SCEV of an expression that have a small positive range (e.g. [0,31]), we would have a SCEV with a fullset as value range. Indeed, in the new rewritten function I tried to better handle the maximum backedge taken count computation when MAX/MIN expression are used to handle the cases where no entry guard is found. Some test have been modified in order to check the new value correctly (I manually check them and reasoning on possible overflow the new values seem correct). I finally added a new test case related to the multiplication by -1 issue on GT comparisons. llvm-svn: 194116
81 lines
3.4 KiB
LLVM
81 lines
3.4 KiB
LLVM
; RUN: opt < %s -scalar-evolution -analyze | FileCheck %s
|
|
|
|
; ScalarEvolution can't compute a trip count because it doesn't know if
|
|
; dividing by the stride will have a remainder. This could theoretically
|
|
; be teaching it how to use a more elaborate trip count computation.
|
|
|
|
; CHECK: Loop %bb3.i: backedge-taken count is ((64 + (-64 smax (-1 + (-1 * %0))) + %0) /u 64)
|
|
; CHECK: Loop %bb3.i: max backedge-taken count is 33554431
|
|
|
|
%struct.FILE = type { i32, i8*, i8*, i8*, i8*, i8*, i8*, i8*, i8*, i8*, i8*, i8*, %struct._IO_marker*, %struct.FILE*, i32, i32, i64, i16, i8, [1 x i8], i8*, i64, i8*, i8*, i8*, i8*, i64, i32, [20 x i8] }
|
|
%struct.SHA_INFO = type { [5 x i32], i32, i32, [16 x i32] }
|
|
%struct._IO_marker = type { %struct._IO_marker*, %struct.FILE*, i32 }
|
|
|
|
@_2E_str = external constant [26 x i8]
|
|
@stdin = external global %struct.FILE*
|
|
@_2E_str1 = external constant [3 x i8]
|
|
@_2E_str12 = external constant [30 x i8]
|
|
|
|
declare void @sha_init(%struct.SHA_INFO* nocapture) nounwind
|
|
|
|
declare fastcc void @sha_transform(%struct.SHA_INFO* nocapture) nounwind
|
|
|
|
declare void @sha_print(%struct.SHA_INFO* nocapture) nounwind
|
|
|
|
declare i32 @printf(i8* nocapture, ...) nounwind
|
|
|
|
declare void @sha_final(%struct.SHA_INFO* nocapture) nounwind
|
|
|
|
declare void @sha_update(%struct.SHA_INFO* nocapture, i8* nocapture, i32) nounwind
|
|
|
|
declare i64 @fread(i8* noalias nocapture, i64, i64, %struct.FILE* noalias nocapture) nounwind
|
|
|
|
declare i32 @main(i32, i8** nocapture) nounwind
|
|
|
|
declare noalias %struct.FILE* @fopen(i8* noalias nocapture, i8* noalias nocapture) nounwind
|
|
|
|
declare i32 @fclose(%struct.FILE* nocapture) nounwind
|
|
|
|
declare void @sha_stream(%struct.SHA_INFO* nocapture, %struct.FILE* nocapture) nounwind
|
|
|
|
define void @sha_stream_bb3_2E_i(%struct.SHA_INFO* %sha_info, i8* %data1, i32, i8** %buffer_addr.0.i.out, i32* %count_addr.0.i.out) nounwind {
|
|
newFuncRoot:
|
|
br label %bb3.i
|
|
|
|
sha_update.exit.exitStub: ; preds = %bb3.i
|
|
store i8* %buffer_addr.0.i, i8** %buffer_addr.0.i.out
|
|
store i32 %count_addr.0.i, i32* %count_addr.0.i.out
|
|
ret void
|
|
|
|
bb2.i: ; preds = %bb3.i
|
|
%1 = getelementptr %struct.SHA_INFO* %sha_info, i64 0, i32 3
|
|
%2 = bitcast [16 x i32]* %1 to i8*
|
|
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %2, i8* %buffer_addr.0.i, i64 64, i32 1, i1 false)
|
|
%3 = getelementptr %struct.SHA_INFO* %sha_info, i64 0, i32 3, i64 0
|
|
%4 = bitcast i32* %3 to i8*
|
|
br label %codeRepl
|
|
|
|
codeRepl: ; preds = %bb2.i
|
|
call void @sha_stream_bb3_2E_i_bb1_2E_i_2E_i(i8* %4)
|
|
br label %byte_reverse.exit.i
|
|
|
|
byte_reverse.exit.i: ; preds = %codeRepl
|
|
call fastcc void @sha_transform(%struct.SHA_INFO* %sha_info) nounwind
|
|
%5 = getelementptr i8* %buffer_addr.0.i, i64 64
|
|
%6 = add i32 %count_addr.0.i, -64
|
|
br label %bb3.i
|
|
|
|
bb3.i: ; preds = %byte_reverse.exit.i, %newFuncRoot
|
|
%buffer_addr.0.i = phi i8* [ %data1, %newFuncRoot ], [ %5, %byte_reverse.exit.i ]
|
|
%count_addr.0.i = phi i32 [ %0, %newFuncRoot ], [ %6, %byte_reverse.exit.i ]
|
|
%7 = icmp sgt i32 %count_addr.0.i, 63
|
|
br i1 %7, label %bb2.i, label %sha_update.exit.exitStub
|
|
}
|
|
|
|
declare void @sha_stream_bb3_2E_i_bb1_2E_i_2E_i(i8*) nounwind
|
|
|
|
declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1) nounwind
|
|
|
|
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32, i1) nounwind
|
|
|