//go:build !purego

package sha512

import "internal/cpu"

func block(dig *digest, p []byte) {
	if cpu.ARM64.HasSHA512 {
		blockAsm(dig, p)
		return
	}
	blockGeneric(dig, p)
}

//go:noescape

#define SHA512ROUND_LAST(i0, i1, i2, i3, i4, rc0, in0) \
	SHA512TRANS(i0, i1, i2, i3, i4, rc0, in0) \
	SHA512H	V7.D2, V6, i3 \
	VADD	i3.D2, i1.D2, i4.D2 \
	SHA512H2	i0.D2, i1, i3

// func blockAsm(dig *digest, p []byte)
TEXT ·blockAsm(SB),NOSPLIT,$0
	MOVD	dig+0(FP), R0
	MOVD	p_base+8(FP), R1
	MOVD	p_len+16(FP), R2
	MOVD	·_K+0(SB), R3

	// long enough to prefetch
	PRFM	(R3), PLDL3KEEP
	// load digest

		return s390x.ACGIJ
	case ssa.BlockS390XCLIJ:
		return s390x.ACLIJ
	case ssa.BlockS390XCLGIJ:
		return s390x.ACLGIJ
	}
	b.Fatalf("blockAsm not implemented: %s", b.LongString())
	panic("unreachable")
}

func ssaGenBlock(s *ssagen.State, b, next *ssa.Block) {
	// Handle generic blocks first.
	switch b.Kind {
	case ssa.BlockPlain:
		if b.Succs[0].Block() != next {
			p := s.Prog(s390x.ABR)

		panic("crypto/cipher: input not full blocks")
	}
	if len(dst) < len(src) {
		panic("crypto/cipher: output smaller than input")
	}
	if alias.InexactOverlap(dst[:len(src)], src) {
		panic("crypto/cipher: invalid buffer overlap")
	}
	if len(src) == 0 {
		return
	}

	// For each block, we need to xor the decrypted data with the previous block's ciphertext (the iv).

  /// be accessed while holding the Block's mu lock. The data vector should only
  /// be accessed after state == FINISHED, and it should never be modified.
  ///
  /// In order to prevent deadlocks, never grab the block-cache-wide mu_ lock
  /// AFTER grabbing any block's mu lock. It is safe to grab mu without locking
  /// mu_.
  struct Block {
    /// The block data.

)

// fuse simplifies control flow by joining basic blocks.
func fuse(f *Func, typ fuseType) {
	for changed := true; changed; {
		changed = false
		// Be sure to avoid quadratic behavior in fuseBlockPlain. See issue 13554.
		// Previously this was dealt with using backwards iteration, now fuseBlockPlain
		// handles large runs of blocks.
		for i := len(f.Blocks) - 1; i >= 0; i-- {
			b := f.Blocks[i]
			if typ&fuseTypeIf != 0 {

			return nil, err
		}

		offset := ei.V2Obj.EcBSize * blockNum
		if offset >= m.size {
			return nil, fmt.Errorf("block %d out of range. offset %d > size %d", blockNum, offset, m.size)
		}
		m.blockOffset = offset
		m.blocks = (m.size + ei.V2Obj.EcBSize - 1) / ei.V2Obj.EcBSize
		if m.blocks > 0 {
			m.blocks--
		}
		if blockNum < m.blocks {
			m.size = ei.V2Obj.EcBSize
		} else {
			m.size -= offset

//
// Property (1) means that blocks sorted by domorder always have a maximal dominant block first.
// Property (2) allows searches for dominated blocks to exit early.
func (t SparseTree) domorder(x *Block) int32 {
	// Here is an argument that entry(x) provides the properties documented above.
	//
	// Entry and exit values are assigned in a depth-first dominator tree walk.
	// For all blocks x and y, one of the following holds:
	//

  EXPECT_EQ(out, B);
  EXPECT_EQ(calls, 4);
  // Remove the blocks from "a".
  cache.RemoveFile("a");
  // Both blocks from "b" should still be there.
  TF_EXPECT_OK(ReadCache(&cache, "b", 0, n, &out));
  EXPECT_EQ(out, b);
  TF_EXPECT_OK(ReadCache(&cache, "b", 8, n, &out));
  EXPECT_EQ(out, B);
  EXPECT_EQ(calls, 4);
  // The blocks from "a" should not be there.
  TF_EXPECT_OK(ReadCache(&cache, "a", 0, n, &out));

	// to finish popping.
	if block.popped.Add(1) == spanSetBlockEntries {
		// Clear the block's pointer.
		blockp.StoreNoWB(nil)

		// Return the block to the block pool.
		spanSetBlockPool.free(block)
	}
	return s
}

// reset resets a spanSet which is empty. It will also clean up
// any left over blocks.
//
// Throws if the buf is not empty.
//