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llvm-project/llvm/test/CodeGen/Mips/llvm-ir/extractelement.ll

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Fix vector splitting for extract_vector_elt and vector elements of <8-bits. Summary: One of the vector splitting paths for extract_vector_elt tries to lower: define i1 @via_stack_bug(i8 signext %idx) { %1 = extractelement <2 x i1> <i1 false, i1 true>, i8 %idx ret i1 %1 } to: define i1 @via_stack_bug(i8 signext %idx) { %base = alloca <2 x i1> store <2 x i1> <i1 false, i1 true>, <2 x i1>* %base %2 = getelementptr <2 x i1>, <2 x i1>* %base, i32 %idx %3 = load i1, i1* %2 ret i1 %3 } However, the elements of <2 x i1> are not byte-addressible. The result of this is that the getelementptr expands to '%base + %idx * (1 / 8)' which simplifies to '%base + %idx * 0', and then simply '%base' causing all values of %idx to extract element zero. This commit fixes this by promoting the vector elements of <8-bits to i8 before splitting the vector. This fixes a number of test failures in pocl. Reviewers: pekka.jaaskelainen Subscribers: pekka.jaaskelainen, llvm-commits Differential Revision: http://reviews.llvm.org/D12591 llvm-svn: 247128
2015-09-09 17:53:20 +08:00
; RUN: llc < %s -march=mips -mcpu=mips2 | FileCheck %s -check-prefix=ALL
; This test triggered a bug in the vector splitting where the type legalizer
; attempted to extract the element with by storing the vector, then reading
; an element back. However, the address calculation was:
; Base + Index * (EltSizeInBits / 8)
; and EltSizeInBits was 1. This caused the index to be forgotten.
define i1 @via_stack_bug(i8 signext %idx) {
%1 = extractelement <2 x i1> <i1 false, i1 true>, i8 %idx
ret i1 %1
}
; ALL-LABEL: via_stack_bug:
; ALL-DAG: addiu [[ONE:\$[0-9]+]], $zero, 1
[DAG] Do MergeConsecutiveStores again before Instruction Selection Summary: Now that store-merge is only generates type-safe stores, do a second pass just before instruction selection to allow lowered intrinsics to be merged as well. Reviewers: jyknight, hfinkel, RKSimon, efriedma, rnk, jmolloy Subscribers: javed.absar, llvm-commits Differential Revision: https://reviews.llvm.org/D33675 llvm-svn: 319036
2017-11-27 23:28:15 +08:00
; ALL-DAG: sh [[ONE]], 6($sp)
DAG: Avoid OOB when legalizing vector indexing If a vector index is out of bounds, the result is supposed to be undefined but is not undefined behavior. Change the legalization for indexing the vector on the stack so that an out of bounds index does not create an out of bounds memory access. llvm-svn: 291604
2017-01-11 06:02:30 +08:00
; ALL-DAG: andi [[MASKED_IDX:\$[0-9]+]], $4, 1
Fix vector splitting for extract_vector_elt and vector elements of <8-bits. Summary: One of the vector splitting paths for extract_vector_elt tries to lower: define i1 @via_stack_bug(i8 signext %idx) { %1 = extractelement <2 x i1> <i1 false, i1 true>, i8 %idx ret i1 %1 } to: define i1 @via_stack_bug(i8 signext %idx) { %base = alloca <2 x i1> store <2 x i1> <i1 false, i1 true>, <2 x i1>* %base %2 = getelementptr <2 x i1>, <2 x i1>* %base, i32 %idx %3 = load i1, i1* %2 ret i1 %3 } However, the elements of <2 x i1> are not byte-addressible. The result of this is that the getelementptr expands to '%base + %idx * (1 / 8)' which simplifies to '%base + %idx * 0', and then simply '%base' causing all values of %idx to extract element zero. This commit fixes this by promoting the vector elements of <8-bits to i8 before splitting the vector. This fixes a number of test failures in pocl. Reviewers: pekka.jaaskelainen Subscribers: pekka.jaaskelainen, llvm-commits Differential Revision: http://reviews.llvm.org/D12591 llvm-svn: 247128
2015-09-09 17:53:20 +08:00
; ALL-DAG: addiu [[VPTR:\$[0-9]+]], $sp, 6
[SelectionDAG] Reverse the order of operands in the ISD::ADD created by TargetLowering::getVectorElementPointer so that the FrameIndex is on the left. This seems to improve X86's ability to match this into an address computation. Otherwise the other operand gets assigned to the base register and the stack pointer + frame index ends up in the index register. But index registers can't encode ESP/RSP so we end up having to move it into another register to meet the constraint. I could try to improve the address matcher in X86, but swapping the producer seemed easier. Several other places already have the operands in this order so this is at least consistent. llvm-svn: 321370
2017-12-23 01:18:13 +08:00
; ALL-DAG: or [[EPTR:\$[0-9]+]], [[VPTR]], [[MASKED_IDX]]
Fix vector splitting for extract_vector_elt and vector elements of <8-bits. Summary: One of the vector splitting paths for extract_vector_elt tries to lower: define i1 @via_stack_bug(i8 signext %idx) { %1 = extractelement <2 x i1> <i1 false, i1 true>, i8 %idx ret i1 %1 } to: define i1 @via_stack_bug(i8 signext %idx) { %base = alloca <2 x i1> store <2 x i1> <i1 false, i1 true>, <2 x i1>* %base %2 = getelementptr <2 x i1>, <2 x i1>* %base, i32 %idx %3 = load i1, i1* %2 ret i1 %3 } However, the elements of <2 x i1> are not byte-addressible. The result of this is that the getelementptr expands to '%base + %idx * (1 / 8)' which simplifies to '%base + %idx * 0', and then simply '%base' causing all values of %idx to extract element zero. This commit fixes this by promoting the vector elements of <8-bits to i8 before splitting the vector. This fixes a number of test failures in pocl. Reviewers: pekka.jaaskelainen Subscribers: pekka.jaaskelainen, llvm-commits Differential Revision: http://reviews.llvm.org/D12591 llvm-svn: 247128
2015-09-09 17:53:20 +08:00
; ALL: lbu $2, 0([[EPTR]])